Sample Question by Students of Class ZCT 104

By noor sawana sabaruddin (79172) 

1. Which of the following statement is/are true?

I. Relativistic mass is not an invariant quantity but rather is dependent on the particle’s speed. (correct)

II. A particle’s relativistic mass decreases with speed. (false)

III. Proper time is not dependent on the choice of inertial frame. (false)

IV. Classical law of momentum conservation is invariant under a Galilean transformation. (true)

A. a      B. a,b        C. a,b,c           D a,b,c,d     E non of the above.

Answer : DIY (Comment: doesn’t sound authentic to me lah)

2. Which of the following statement is/ are true?

I. Galilean transformation is valid on classical laws Newtonian mechanics. (true)

II. Hubungan di antara momentum klasik dan momentum relativity tidak boleh dikaitkan di antara satu sama lain secara matematik. (false)

III. All conservational laws in physics are invariant under Galilean transformation. (false)

IV. The expression of classical definition of momentum is invariant under Lorentz transformation. (false)

A. I      B.  I,II        C. II, III, IV       D.  I,IV       E. non on the above. 

answer : DIY

reason.

~ mmtum klasik dan relativity  BOLEH di hubungkan antara satu sama lain.

~ G.T hanya teraplikasi dlm Huk. MEKANIK shj, tetapi  L.T   teraplikasi dlm semua hukum FIZIK.

~ Newton relation for momentum CANNOT be invarient under L.T

(Comment: doesn’t sound authentic to me lah)

3. Observer X is standing at ground with respect to observer Y who is standing in a moving train. Which observers’ statement on the simultaneity of two events is taken as a valid one?

A.X’s      B.Y’s     C. both X and Y’s claim are equally valid   D. non of the above.

ANS:   B and A. their are equally valid because simultaneity is NOT an absolute concept but a relative one, depends on the state of motion.

By noor masdiana bte md.said

4. Which one of these statements that the two observers O and O' DO NOT AGREE on?

I. The time interval between events that take place in the same position in one of the frames.

II. Whether two events occurring at different locations in both frame are simultaneous.

III. Their relative speed of motion v with respect to each other.

IV. The simultaneity of two events which take place at the same position and time in some frame

A. I,II,III B. I,IV C. III,IV D. I, II E. IV

5. A box is measured by an observer on the earth to have a rest length of L. Now, the box is in a spacecraft which moves with the speed of u = ³√ (c/2). What is the length of the box as measured by an astronaut who is also in the same spacecraft?

A. L          B. 2L          C.L/2          D.4L          E. none of the above 

answer : DIY

By Chan Tang Yoong (81824)

6. There are 4 planes flying with same constant speed (c/2) to the North (N), West (W), East( E) and South(S). Which of the following statement(s) is(are) true?

I.  The rate of time flow plane N is the same as that in plane (S), but is slower than that in plane (W).
II. All the 4 planes have the same rate of time flow.
III. The plane W have the slowest rate of time flow.
IV. The plane E has the slowest rare of time flow.

A. I,IV.      B. II.      C. III.      D.I.         E. Non of the above.

Answer : DIY

(Comment: doesn’t sound authentic to me lah. Looks like it is copied from somewhere…)

7. If you are traveling in a train at a speed c/2 (relative to ground), what speed would you observe on a bird that flies with a speed of 0.1c relative to an observer on the ground? Assuming that the bird is flying towards the train from the opposite direction.
   
   

A.0.60c   B.0.57c   C.0.58c   D.0.55c   E.0.56c

(Comment: doesn’t sound authentic to me lah. Looks like it is copied from somewhere…)

By lim kok yong ( 82441/04 ), loh chon foong ( 82454/04 ), tong kim suan  ( 82762/04 ) 

8. Jika satu zarah bergerak dengan laju 0.9c, jisimnya ialah m1. Zarah itu dibawa ke angkasa lepas dan dipecut kepada laju malar 0.9c, jisimnya menjadi m2. Diketahui jisim rehat zarah ialah m0. Susunkan tertib menaik bagi jisim zarah itu.

A)     m0< m1< m2 B)     m2< m1< m0 C)     m0< m2= m1 D)     m1= m2 <m0 E)      tiada jawapan di atas

Answer : DIY

9. Pernyataan yang manakah tidak benar mengikut teori fizik klasik.

1) cahaya yang berkeamatan tinggi akan menyebabkan tenaga kinetik elektron bertambah.

2) tenaga adalah selanjar dan tidak boleh dibelah.

3) cahaya ialah gelombang dan tidak mengandungi tenaga diskrit.

4) apabila cahaya membekalkan tenaga kepada elektron, masa diperlukan untuk elektron disingkirkan.

A)    1 dan 2

B)     2 dan 3

C)    3 dan 4

D)    3 sahaja

E)     tiada jawapan

Answer : DIY

10. Jika fungsi kerja bagi suatu logam ialah 4.00x10^-19 J. Frekuensi cahaya yang manakah boleh menyingkirkan elektron daripada permukaan logam itu.

A)    7.74*10^-5 eV Hz

B)     5.81*10 ¹⁴ Hz

C)    9.98*10^-5 eV Hz

D)    4.84*10 ¹⁴ Hz

E)     tiada jawapan

Answer : DIY

(Comment: doesn’t sound authentic to me lah. Looks like it is copied from somewhere…)

11. Jika permukaan logam disinari dengan cahaya monokromatik yang mempunyai keamatan, I1 dan jika permukaan logam disinari dengan cahaya yang sama panjang gelombang tetapi keamatannya ialah I2. Diketahui I2 > I1. Pernyataan yang manakah benar.

I) tenaga foton cahaya bertambah.

II) fotoarus bertambah.

III) tenaga kinetik maksimun fotoelektron bertambah.

IV) tenaga foton cahaya tidak berubah.

A)   I, II dan III sahaja

B)     II sahaja

C)    II dan III sahaja

D)    II dan IV sahaja

E)     tiada jawapan

Answer : DIY

(Comment: doesn’t sound authentic to me lah. Looks like it is copied from somewhere…)

12. Pernyataan yang manakah benar mengenai kuantum cahaya.

1) tenaga satu foton tidak dipengaruhi oleh keamatannya.

2) laju fotoelektron bertambah apabila keamatan sinaran bertambah.

3) fotoelektron tidak semesti tidak akan disingkirkan, apabila keamatan cahaya adalah rendah.

4) fotoelektron bergerak lebih laju jika disinari cahaya yang frekuensi lebih rendah daripada frekuensi ambang.

A)    1 sahaja B)     2 dan 3 sahaja C)    1 dan 3 sahaja D)    1, 3 dan 4 sahaja E)     tiada jawapan

Answer : DIY

Authentic question by 1. Hadijah Awang Mahmud ( 52488/99 ), 2. Masitah Wahidon ( 72084/02 ), 3. Hazura Hashim ( 72060/02 ), 4. Sharifah Nurah Sayed Dol Islam ( 58861/00)

13. Minimum requirements for photoelectrons to be ejected out from the metal surface :

( Syarat-syarat minimum untuk fotoelectron-fotoelektron dikeluarkan dari permukaan logam )

i. Kinetic energy, Kmax >0 ( Tenaga kinetik, Kmax>0)

ii. υ = υ₀

iii. υ > υ₀

iv. hυ≥W₀

(a) I, II & IV

(b) I & III

(c) II & IV

(d) None of above

Answer : B (YTL’s comment. This question is authentic judging from the fact that i have not seen them before. I would like to comment on the option i: The requirement of Kmax > 0 is not a requirement to get the electron kicked out from the surface, but a consequence. Also, option III and option IV are actually equivalent statements. Option II is a bit ambiguous to be an ‘yes’ because u r asking for ‘minimal requirement’. So I am not really sure if option II should be taken as yes or no. in any case, my answer to this question is III and IV. I think option II should be replaced by some other non-ambiguous statement to avoid confusion )

By noor sawana sabaruddin (79172)

14. "plank`s hyphothesis removes the unphysical divergent high frequency predicted by classical theory". What statement is (are) true in the Planck theory?

a.  the higher the frequency give smaller the quantum of energy. (I suppose u mean “the higher the frequency of the light, the smaller the quantum energy of a photon is”)

b. the frequency of black body radiation radiated is increased accordingly when the quantum gaps between the oscillators increases (I have reinterpret yr original statement …)

c.  A blackbody has only a finite amount of energy so it can produces an extremely high ' f ' quantum jump. (aiyo…don’t know how to reinterpret or correct this statement lah…So actually I am also not sure if this statement actually makes sense or not.)

d. the energy of macroscopic scale seems to vary continuously (this statement is correct)

A a,b        B c,d         C a,c ,d           D b,c,d           E b,d

Ans. E reason :BB cannot supply to produce an extremely ' F '. the higher ' f '  give the higher quantum

15. What of the related between photoelectric(PE) and Compton Effect(CE)?

a. PE can behave as a particle and CE exhibit wavelike behavior.

b. The CE is change in wavelength of high energy EM radiation when the scatter off electron

c. X-ray energy scale involved is much higher than PE

d. a photon give up part of its energy in CE, but in PE photon give up all of its energy to electron (this is a correct statement)

A a,b         B b,c           C a, c, d                  D a,b,d               E  b,c,d

(YTL’s comment: this question is not well asked. For a, one cannot says PE or CE behaves like wave or particle, because they are experiments. How could an experiments behave like wave or particle? In b, you should say: “in CE, the high energy EM radiation would change in its wavelength when scattered off by an electron. This is a correct statement.”

Statement c appeared ambiguous. The correct statement is “the energy scale of an x-ray photon is similar or higher than the energy scale involved in a typical PE experiment.” The energy scale in aCE corresponds to the equivalence of the Compton wavelength, h/mc. In CE, the wavelength of the x-ray used have to be at the same scale or smaller compared to the Compton wavelength. ” )

16. What’s the most important significance of the Compton Effect experiment?

a.  To confirm that the energy of the quantum of light is proportional to the frequency of the wave model of light (Nop. Despite a correct statement, it is not the most important significance of the Compton experiment)

b.  To confirm that the radiant energy of light is quantized into concentrated bundle (Nop. Despite a correct statement, it is not the most important significance of the Compton experiment. This statement would be a correct choice if photoelectricity is referred.)

c.  To confirm that EM radiation has both wave and particle properties (nop. The correct statement is “To confirm that EM radiation has particle properties”)

d.  To confirm that the X-ray energy is transferred from photon to Kinetic energy of electron (err…this is a correct statement but not the most important significance of the Compton experiment)

17. What is (are) the correct statement(s) about X-ray?

a.  Part or all of  the kinetic energy of the moving electron is converted into X ray photon (true)

b.  electromagnetic radiation is emitted when free electrons absorb part of the photon energy (false statement. Free electron can’t absorb photon’s energy by itself)

c. the production of x ray can be considered as a photoelectric process (incorrect)

d.  The shortest wavelength in the x-ray spectrum is the same for different material (true).

A. a,b    B.  b,c,d,       C.  a,c,d          D.  a,c        E. none from above

By Noor masdiana bte md.said(mas), 83762

18. Which of these statements are true?

(a) Rayleigh-Jeans law is reasonable at short wavelengths (you should replace ‘reasonable’ by ‘behaving physically’ to make the meaning of this option less ambiguous)

(b) Rigel  (the blue star) is hotter than Betelguese (red star) because of the position of the peak wavelength in their black body spectrum

(c) According to Rayleigh-Jeans law the average energy is given by the equipartition theorem

(d)Based on experimental data, the probability of excitation in the oscillator in a blackbody is low at short wavelengths

A. a and b                                C. a B. none of the above                  D. b, c and d

ANS: DIY 

19. Which of these statement are correct?

(a) We conclude that light to behave like a wave when we find that the light from the sun arrives to the Earth after 8 minutes it was emitted. (err…nop. .Logically we cant make such conclusion based on this observation. )

(b) When we consider light to behave like a particle there is a time lag for the electron being emitted from the surface of the metal in a PE experiment. (this is an false statement. If we consider light as particle there would be almost no time lag.)

(c) Photoelectricity occurs at the same energy scale because the process to produce X rays is just inverse process of photelectricity (this statement appeared ambiguous. It should be corrected to “Photoelectricity occurs at the same energy scale as the x-ray production because X rays production is the inverse of the photelectricity process”. This is a false statement.)

(d) X rays is affected by electric and magnetic fields. (this is a false statment)

A. c and d                                 C. a,b,c and d B. a and b                                 D. a

ANS: DIY

By Norhidaya binti Zakaria, 74483/3 

20. Which of the following statement are false?

I)The energy level of the electrons in atomic orbit is quantized (this is a correct statement)

II)The energy state is negative because it is not a bounded system (this is a false statement. Energy state negative means its is a bounded system.)

III)E=0 means the electron is free from the bondage of the nucleus' potential field. (this is a correct statement)

IV)Electron at high n is tightly bounded to the nucleus by the EM force. (this is a false statement)

A)I,II,IV B)II,IV C)I,III,IV D)I, II, III, IV

ANS: DIY 

21. The Bohr model was developed specifically for hydrogenic atom. It has three ingredients. What are they?

I) An application of Newton's second law (Being a hybrid theory, Bohr’s theory assumes Newton law in the ‘mechanical stability” postulate. So this is a true statement.)

II) The expression for total energy (err…this is an ambiguous statement. It has an expression of the total energy, but so what? Any theory can supply expression of total energy. So does the expression of the total energy an ‘ingredient’ to the theory? So strictly speaking this is not a correct option to this question despite being a correct statement.)

III) the angular momentum postulate (to pose an option to the question, u got to be more specific. U got to mention that it is quantized angular momentum postulate.)

IV) An application of classical theory (to make this option less ambiguous, its best be replaced by ‘It assumes the validity of classical electromagnetic theory”. Then this would make this statement unambiguously false.’)

A)I,II

B)III,IV

C)I, II, III

D)I, II, III,IV

ANS: DIY

By Tan Seng Yee, 74623

22. Which of the following statements are true?
    
    i. Thompson suggestion of Plum Pudding Model is the first postulate on the atom. (err… its difficult to validate such a statement. I suppose there must be many thousands of other postulates on the atom long before Thompson. So I would not take this as an true statement)

ii. Rutherford suggested Planetary model. (True)

iii. De Broglie confirmed that the wave nature of electron in which it undergoes Bragg’s diffraction. (its Bragg who confirm this, not de Broglie. dB only made the postulation, not the one who confirms it. So this is a false statement)

iv. Compton had done an experiment revealing the particle nature of X- ray. This discovery confirmed that electromagnet radiation has both wave &
particle properties. (Err…the Compton experiment per se confirms only the particle nature of light, but not confirm them to be both. So the statement would be true only if you correct it to be “Compton had done an experiment revealing the particle nature of X- ray. This discovery confirmed that electromagnet radiation has particle properties.”)

A. I B. i,ii,iii C. i,iii,iv D. i,ii,iv E. not in the choices A, B, C, D

(Says Seng Yu:) Actually I have other statements instead of above one:

*Max Planck-developed a theory of blackbody radiation that lead to an equation for the intension of radiation. (To be more specific, you should ask “Max Plan k -developed a theory of blackbody radiation that lead to an correct equation for the intension of black-body radiation that conforms with the experimental observation”)

*Einstein-space & time now becomes state-of-motion dependent. (correct statement)

*Michelson & Morley-They did an experiment which render untendable the hypotesis of the ether. (this statement is taken directly from past year lah, not authentic.)

*Heisenberg-uncertainty principle shows that a particle is represented by a wave packet/pulse. (err…this statement is a bit ambiguous. Logically I am not sure if this statement is true or false lah. May be the logics has to be reversed, ie. Because particle is like wave, therefore there obey the uncertainty principle.)

*Davisson & Gremer-confirmed the wave nature of electron in which it undergoes Bragg’s diffraction. (correct, but I suspect this statement is again copied from past year question lah.)

*de Broglie-particle has intrinsic wave properties. (A correct statement)

I think…this type of question require student to know the contributions of the physicist

Subjective

Why are the Thompson & Rutherford’s atomic models cannot be accepted? (err…this is not a correct way to ask the question. They are actually accepted once, except that there are incompatibility between the models with experiments and/or theoretical expectation. So one should ask the question in a more robust manner:“ Why are the Thompson & Rutherford’s atomic models not completely acceptable?”)

Ans: Thompson’s Plum Pudding Model was falsified by the Rutherford’s experiment in which some of the alpha-particles bombarding the atom were reflected in 180degree.

Rutherford Planetary model is falsified by the infrared catastrophe. (err…it would be difficult to say that the model is falsified by the infrared catastrophe, as the latter is only an theoretical expectation, which may not be absolutely robust. The best one can say is that “Rutherford Planetary model is predicted to have infrared catastrophe, which is an unacceptable feature to any physical theory.” Whether one can take this statement as a valid ‘falsification’ to the model is subjected to argument.)

3. What is the central of quantum physics?
Ans: Aarticle & wave properties of electromagnet radiation.

(Whoops, this appear to be an extremely oversimplifying statement.)

23. Which of the following statement is true about the Plum-pudding model by Thompson?

i. Plum-pudding model fails to explain the emission & absorption line spectrum from atoms because it predicts only a single unique emission frequency.

ii. Rutherford’s scattering experiment fails to falsify the Plum-pudding model. (err…well, it is correct to say that Rutherford’s experiment falsifies the plum pudding model. So the negative to this statement should be a true statement. )

iii. Plum-pudding model cannot explain the 180 degree back-scattering of alpha particle seen in Rutherford’s scattering experiment. (true)

iv. Rutherford’s scattering experiment explains the large deflection of alpha particle is caused by a close encounter between alpha particle and the
diffused distribution of the positive charge of an atom. (Nop. The Rutherford experiment DOES NOT EXPLAIN the large deflection but merely observes them to be so. It is the Rutherford’s planetary model that does the explanation.)

a. I b. i,ii,iii c. i,v d. i,iii  

24. There are 3 postulates stated by Bohr in his hydrogen-like atomic model. Which of the following statements below are included in the postulates?
    
    

i. It is mechanical stability (where the Coulomb attraction is equal to centripetal force.) (true)
ii. There is infinite orbit which is possible in classical mechanics. (false)
iii. It is only possible for an electron to move in an orbit that contains an integral number of de Broglie wavelength. (true)

iv. An electron moving in allowed orbit does not radiate electromagnet energy despite the fact that it is constantly accelerating. (true)

a. i,iii,iv b. ii,iii,iv c. i,ii,iv d. i,ii,iii

25. There are the same flaws in the Thompson’s Plum-pudding model as well as Rutherford’s planetary model. What are they?
    
    

I) They cannot explain the pattern of discrete spectral lines. (true)

II) The prediction of unique oscillation frequency in the plum pudding model is falsified by the fact that observationally light spectra from all atoms shows sets of discrete spectra lines correspond to many different frequencies. (true)

III) Both’s model has the defective feature of Infrared Catastrophe. (true)

(IV) The Rutherford scattering experiment showing large angle deflection of alpha particle falsified both of the models proposed by Thompson & Rutherford. (this is an false statement as the experiment only falsifies Thompson’s mode but not the Rutherford model)

By nursyazura bt. Khari, 74505/03

26. Which of the following statement(s) is (are) true regarding the basic properties of atoms?
    
    1) Atoms are of macroscopic size, ~10^-10 m. (this is an oxymoron statement. A size of the order of -10 is necessarily of microscopic scale. From an examination question design point of view such a statement should be avoided by replacing them with a consistent statement. )

2) Atoms are not stable. (false)
3) Atoms contain negatively charges, electrons, but are electrically neutral. (true)
4) Atoms emit and absorb EM radiation. (true)

A) 1,3 and 4 B) 1,2 and 4 C) 3 and 4 D) Non of the above

ANS: DIY

By Noor Syuhada Binti Mat Serat, 74458/03, industrial chemistry

27. . Which is (are) the correct statements about photoelectricity (PE) and X-ray:

I.                     Energy is transferred from kinetic energy of electrons to photons in PE. (true)

II.                 In X-ray production, work function of the metal surface is not approximately ignored, whereas this is the opposite in PE. (false)

III.               Energy scale is not the same in both PE and X-ray. (true)

IV.              X-ray is an exothermic process. (Some comment of caution: I suppose the term exothermic is referred to processes in which energy is released when molecules/atoms rearrange themselves in an physical process involving the change of states. If this definition of exothermic is such defined then this is a true statement. )

28. Choose the false answer. 

A. the energy gap between adjacent energy levels become smaller when the n increased (Comment: this is true in the special case of Bohr’s hydrogen model. Generally this is not the case (such as in the particle-in-the-box model).)

B. the increase in the quantum number n in Bohr’s atom means the increase of the positive energy. (err…this statement sounds a bit redundant as it may give rise to possible confusion of whether there is other thing called the “negative energy”. I would put it simply as ‘the increase in the quantum number n in Bohr’s atom means the increase of the energy of the atomic state’ to make the statement a true statement.)

C. when n approach infinity, the energy states become infinity. (this is a false statement.)

D. Free electron is the electron which is not in the bounded system. (this is a true statement.)

ANS: DIY

By Ahmad Zainal b. Zamil Abdin, 82259.

29. Which statement is (are) true according to classical point of view regarding photoelectricity?

I. Electron should absord energy continuously from the electromagnetic waves. (true in classical theory) 
II. At low intensity, a measurable time interval should pass between the instant the light is turned on and the time an electron is ejected from the metal. (true in classical theory)

III. There should be a relationship liking the frequency of the light used in the experiment with the electron’s kinetic energy measured. (false in classical theory)

IV. Electron should be ejected from the metal only if the light frequency is above certain threshold value, as long as the light intensity is sufficiently high. (false in classical theory)

A. I, II B. II, III C. I,IV D. II only E. Non of the above

ANS: DIY 

30. Based on the formula of K_max + work function = hf, which statement(s) in the following is (are) true?
    
    

I. K_max is dependent on the light intensity (false)

II. The maximum kinetic energy of any one electron depends only on the light intensity and the work function (false)

III If the light intensity is doubled, the number of photons arriving per unit time is doubled, which doubles the number per unit time at which photoelectrons are emitted. (true)

IV. For a given metal surface the maximum kinetic energy of the photoelectrons is not fixed for a given light frequency and intensity. (false)

A. I, II B. II, III C. I,IV D. II only E. Non of the above

By Norazura binti nen, 74477/03

31. When dealing with photoelectrons, a plot of

a) e times the stopping potential against photon frequency is a straight line for each metal.

b) Photocurrent against potential is a straight line of slope h for each metal

c) Photocurrent against incident intensity is a straight line of slope h for each metal

d) Incident intensity against photon frequency is a straight line of slope cutoff for each metal

e) None of these

(Comment: err…again I suspect this question is not original lah. Please correct me if I am wrong.)

By vun tze woei, 74658/03

32. Which of the following is(are) true?

i.  Stopping potential, Vs is dependent on the intensity of the radiation.

ii. Different materials have different cut-off frequency, fo.

iii. An identical material can have many Vs values.

iv. Frequency below fo gives no PE effect but the PE effect occurs when a highly intensed   radiation is shined on the metal surface.

A. i, ii        B. ii, iii       C. ii, iii, iv      D i, iv      E. none from above (ANS: DIY)

33. In PE effect,

i.  there is no time lag

ii. photoelectrons can be kicked out from the metal surface at any intensity.

iii.Kmax is dependent on the frequency of the radiation.

iv. Vs is also dependent on the frequency  of the radiation.

A. i        B. ii, iv       C. i, iii, iv        D. i, ii, iii      E.none from above. (ANS: DIY)

(comment: these questions (Q32,33) were only received on 18.2.05 the day test II takes place. Despite that it is a bit too late I still put them up as an encouragement to motivate students to send in more questions.)

By Teh Kheng Hock 82737; Wong Chee Hong 82227

34. In an interstellar space pod race, two space pods we leading the chasing pack by some distance. It is without a doubt that either one of them would be the victor. As they near the finishing line, space pod A, piloted by Alex Yoong, is leading, with only 500 m from the finish line, with a speed of 0.87c. Following close behind is space pod B, piloted by Karamjit Singh, 600 m from the finishing line, with the speed of 0.92c. Time seemed to be at a stand still as fans hold their breath to see who crosses the finishing line first. Assume that the two space pods’ speeds are constant till the end, which space pod will prove the winner?

A. Space Pod A in relativistic view, Space Pod B in classical view;

B. Space Pod B in relativistic view, Space Pod A in classical view;

C. Space Pod A in relativistic view, Space Pod A in classical view;

D. Space Pod B in relativistic view, Space Pod B in classical view;

E. Both of them cross the finishing line together.

Our answers to the above questions would be : B

Because, whoever who needed the shortest time to reach the finishing line would definitely finish first.. s=vt, t=s/v.With classical calculations, A’s time would be shorter. However, in relativistic view, the distance is shortened by the lorentz factor. I assumed the speed, v, to be constant at both views..

I hope you understand what I mean, sir…I also seriously do not know if my question is correct at all.. am just trying, albeit too late..

(comment: hmm…as a fact I do not go thru the calculation and argument for the answer. Lets leave it to the reader to justify what u say. My comment is: if this is indeed an authentic question from you then bravo, it’s a very creative question, at leastfor the phrasing part.)

35. Which of the following statements is (are) TRUE?

I. If one is able to fly at near the speed of light, in the opposite direction of the

earth’s rotation, according to time dilation, he should be able to travel back in

time. (F)

II. Likewise, if one flies near the speed of light, along the earth’s rotation, he or

she should be able to travel to the future. (F)

III. The rest mass of an object is always smaller than its relativistic mass. (T)

IV. The relativistic mass of an object depends on its speed and time only. (err…to be more precise u should say “The relativistic mass of an object depends on the state of motion in the frame it is observed”, then will then make the question a true statement. It is not quite true to say that the relativistic mass does not depend on the time it experience as time is an integral part of the fabric of space and time.)

A.I and II

B.III only

C.III and IV

D.I, II and III

E. None of the above.

36. It is impossible to achieve a velocity which exceeds the speed of light because:

I. As the object approaches the speed of light, c, it’s length would contract. If it

reaches c, the object would thus have no length at all. (comment: err….in realistic situation we would never reach c but only approach to that limit closer and closer.So the sentence “If it

reaches c, the object would thus have no length at all” seems to be only correct as a theoretical discription but never realise in practice. Any way such a statement is still considered a validly true statement)

II.As the object approaches the speed of light, its mass would increase; thus, if it

reaches c, the object would have infinite mass, which is impossible. (T)

III. To reach the speed of light, much energy is needed, and subsequently, to reach

the speed of light, infinite energy is needed, something of which, is impossible. (T)

IV. According to the time dilation effect, it will take infinite time to obtain or go

over the speed of light. (err…seems to be a true statement but the wording have to modify a bit to, say, “According to the time dilation effect, it will take infinite time to reach the speed of light.”

A. I and II

B. I , II and III

C. III only

D. I, II, III and IV

E. None of the above

ANS: B. I came up with this question remembering the tutorial session you had with us :D kinda un-authentic.. I apologize for that....(comment: it’s considered an authentic question, at least it shows that u do listen while in the tutorial class. A Plus to you. =) )

37. Which of the following statements is(are) true?

I. The laws of quantum mechanics are only valid in the atomic domain (F)

II. The laws of classical physics are only valid in the classical domain (T)

III. The laws of quantum mechanics are valid in a domain where atomic and

classical domains overlap. (T)

IV. The laws of classical physics are valid in a domain where atomic and classical

domains overlap. (F)

A. I and II

B. III and IV

C. I, II, III and IV

D. I, II and III

E. None of the above.

Question by: 1.Hadijah Awang Mahmud ( 52488/99 ); 2. Masitah Wahidon ( 72084/02 ); 3. Hazura Hashim ( 72060/02 ); 4. Sharifah Nurah Sayed Dol Islam ( 58861/00 )

38. When a combination of laser light from Nd:YAG & Nd:Glass hitting to a plasma medium, it accelerate electrons & oscillate it in velocity so near to c. The value of kinetic energy produced is 400MeV. How long is its de Broglie’s wavelength ( for a single electron ) ?

( Apabila cahaya laser dari gabungan Nd:YAG dan Nd:Kaca difokuskan ke dalam satu medium plasma, electron dipecutkan & dihayunkan dalam halaju yang sangat hampir kepada c. Tenaga kinetik terhasil adalah 400MeV. Berapakah panjang gelombang de Broglienya ? )

Answer/Jawapan : 7.76 X 10^-14 m

39. Using VULCAN pulsing laser in 1ps time & wavelength 1μm to shoot a plasma medium containing He gas. So, what is the value of energy necessary for an electron inside He gas to be an ion ?

( Jika menggunakan laser terdenyut VULCAN dalam tempoh 1ps pada jarak gelombang 1 μm untuk menembak satu medium plasma mengandungi gas He, berapakah tenaga yang dipakai oleh elektron gas He untuk mengion ? )

Answer/Jawapan : 2733eV atau 2.7333 X 10^-16 J

40. Questions based on Cassini-Huygens’s mission to Saturn and it’s largest moon, Titan by NASA, ESA and ASI. Cassini is the orbiter spacecraft and Huygens is the probe sent to Titan.

(Soalan berdasarkan Misi Cassini-Huygens ke Planet Zuhal serta bulannya yang terbesar, Titan oleh NASA, ESA dan ASI. Cassini adalah kapal angkasa pengorbit manakala Huygens adalah probe yang dihantar ke Titan )

(a)On January 14, 2005, Robert C. Byrd Green Bank Radio Telescope in West Virginia, USA has detected Huygens’ carrier signal shortly after the probe began its descent through Titan’s atmosphere. It’s happened on 11:25 CET ( take it as Earth Time. ).

( Pada tanggal 14 Januari 2005, teleskop radio Robert C. Byrd Green Bank di Virginia Barat, AS telah mengesan isyarat dari Huygens sejurus selepas prob tersebut memulakan kemasukannya ke atmosfera Titan. Ia berlaku pada pukul 11:25 CET ( waktu Bumi )

Calculate :

(i) Saturn time if the signal from Huygens’s Probe traveled to Earth in 1 hour and 14 seconds.

( Masa di Planet Zuhal jika isyarat dari Huygens bergerak ke Bumi dalam tempoh 1jam 14minit )

(ii) How fast was the signal traveling from Saturn to Earth ?

( Using the same signal transfer time as in (i). Considering Saturn frame is including Titan & Cassini-Huygens )

( Berapakah kelajuan isyarat bergerak dari Zuhal ke Bumi ? Gunakan masa perpindahan isyarat yang sama seperti (i). Anggapkan rangka rujukan Zuhal adalah merangkumi Titan serta Cassini-Huygens )

( Att : All times are written in 24-hours system not am/pm system. )

(Perhatian : Semua waktu ditulis dalam sistem 24-jam, bukannya sistem am/pm )

Answers : (i) Pukul 10:11 pagi

(ii) V=0.99999974c

(b)On this case, Huygens probe has landed on Titan’s surface. Saturn-Earth distances is 8.5 4 AU ( Asronomical Unit ) & Saturn-Titan distances is 1,221,830 km. If the landing signal from Huygens was arrived on Earth by the same velocity as the answer for (a) (ii), what is Titan-Earth distance according to the signal in km ? Take as Titan, Saturn & Earth are in stationary state and assembled in the same line.

( Pada kes ini, prob Huygens probe telah mendarat pada permukaan Titan,

Jarak Planet Zuhal – Bumi adalah 8.54 AU (Unit Astronomi) & Saturn-Titan pula sejauh 1,221,830km. Jika isyarat pendaratan daripada Huygens sampai ke Bumi pada halaju yang sama dengan jawapan di (a) (ii), apakah jarak Titan-Bumi berdasarkan isyarat, dalam unit km ? Anggap Titan, Zuhal dan Bumi dalam keadaan pegun dan tersusun pada satu garis yang sama. )

( 1AU= 149, 597, 870. 691km )

Ans/Jawapan : 290, 988. 6936km

(comment: seemingly an interesting question to try out. Please feed back if you are not totally agree with the answer provided.)

41. Pick statements that are true for UV and IR Catastrophe :

( Pilih pernyataan yang benar bagi malapetaka UV dan IR )

I) UV Catastrophe describing mismatch that happened in the Rayleigh-Jeans Law of blackbody radiations while IR catastrophe describing insufficiency of Rutherford model for atom.

( Malapetaka UV menggambarkan ketidakserasian yang timbul dalam Hukum Rayleigh-Jeans untuk Sinaran Jasad Hitam sementara Malapetaka IR menggambarkan ketidakberkesanan model Rutherford untuk atom )

II) In IR catastrophe, Rutherford Model of Atom has a fatal flaw according to classical EM.

( Dalam Malapetaka IR, Model Atom Rutherford mempunyai kegagalan fatal berdasarkan EM klasik )

III) A major disagreement happened between theoretical prediction and experimental results at short wavelength caused UV catastrophe in Rayleigh-Jeans Law.

( Ketidaksetujuan yang besar berlaku di antara ramalan teori dan keputusan experimen pada panjang gelombang yang pendek menyebabkan malapetaka UV pada hukum Rayleigh-Jeans )

IV) Rutherford Model of Atom can’t explain the discrete spectrum, thus causing IR catastrophe

( Model Atom Rutherford tak dapat menjelaskan spektrum diskrit, maka menyebabkan Malapetaka IR )

1. I, III & IV
2. II & IV
3. I, II & III
4. I, II, III & IV

  By SOFIAH BINTI MOHD AMIR, 82689/04

(Comment: Sofiah admitted that the questions she submuitted are designed by her (by making reference to some sources)except question the second question.

42. Which of these statement(s) shows exactly the failure of explaining the nature of the blackbody radiation of classical energy theory

I.          A continuous spectrum of radiations is emitted by the object.

II.        The peak of the intensity distribution shifts to shorter wavelength.

III.     The total energy emitted from an object increases with temperature

IV.     The charges particle in the atoms near the surface accelerated with various amount of thermal energy.

A. 1,11 B.        11,111 C.       111 D.       1,11,111,1V E.        None of the above

43. Which of the following statement(s) is true about photon

A.       Photon is a particle with positive charge

B.        Photon is a particle with negative charge

C.       Photon is the electron which is produced when light is incident on a metal

surface

D.       Photon is a quantum of electromagnetic wave

E.        None of the above

44. If the frequency of the incident light remains constant but its intensity is double..

I.          The maximum kinetic energy of the photoelectrons remains constant

II.        The maximum kinetic energy of the photoelectrons will increases

III.     The photoelectric current will remain constant

IV.     The photoelectric current will increases

A.       1,11 B.        11,111 C.       111,1V D. 1,1V E.        None of the above

45. X-ray and UV light..

A.       Have different velocities

B.        Have the same wavelength

C.       Are deflected by a magnetic field

D.       Can be detected by photoelectric plate

E.        None of the above

46. Which of these statement(s) is true

I.          The de Broglie wavelength of electron can be controlled by the voltage of the electron gun

II.        Electrons can be focused by using the electronic or magnetic field

III.     Electrons can be accelerated by electric field

IV.     Electrons is quantized (comment: err.. this statement is diffuclt to justify. What exactly you mean by the the term ‘quantised’? You have to be specific here. For example, does the de Broglie’s wavelength of the electron quantised? The speed? So you got to be more specfic here. )

A.       1,11,111

B.        1,111,1V

C.       11,111,1V

D.       1,11,111,1V

E.        None of the above

Disediakan oleh farah ha num binti mohd noh 82328

47. Bohr telah mengemukakan 4 postulat dalam menghasilkan model atomnya. Postulat-postulat itu adalah berdasarkan teori klasik. Antara teori-teori di bawah yang manakah adalah berkaitan dengan teori bohr.

I Maxwell II Planck III De broglie IV Thompson

A I,II,III B III C II,III D semua diatas E tiada jawapan

(comment: Sebenarnya bukan semua postulat itu adalah berdasarkan teori klasik, misalnya, postulat tenaga foton = beza paras tenaga dalam orbit adalah berdasarkan postulat Einstein. Begitu juga de Broglie’s punya postulat bukanlah daripada teori ‘klasik’. Kenyataan bahawa “Maxwell punya teory ada kaitan dengan teori Bohr” adalah terlalu umum untuk dikatagorikan sbg ya atau tidak.)

48. Berikut yang mana adalah benar mengenai x ray spektrum

I spektrum yang terhasil adalah continuos.

II metal yang berbeza memberikan l_min yang berbeza pada beza keupayaan yang sama.

III nilai l yang kurang daripada l_min tidak akan menghasilkan x ray.

(comment: kenyataan ini adalah kurang jitu dan mengelirukan. Misalnya, apakah definasi l yang dimaksudkan di sini? Di sini anda kena membezakan kesan fotoeletrik drp kesan penghasilan x-ray.)

IV beza keupayaan yang semakin bertambah akan menambahkan nilai l_min.

A I,II,II B II,III C I,III D semua diatas E tiada jawapan

49. Yang mana adalah betul

I RJ cuba menjelaskan BB dengan menganggap hole adalah pemantul sinaran EM yang menghasilkan gelombang pegun (eh..apa dia “hole” yang dimaksudkan di sini?...)

II planck anggap gelombang pegun yang terhasil pada setiap pengayun harmonic hanya menyerap dan memancar tenaga dalam bentuk selanjar.

III RJ hanya benar pada l yang besar

IV bagi frekuensi yang rendah, teori planck adalah bertepatan dengan teori RJ.

50. Yang mana adalah benar mengenai teori pengkuantuman cahaya oleh Einstein

I tenaga sinaran EM merupakan suatu kuanta yang dipanggil foton

II kadar penghasilan elektron yang dipancarkan oleh 1 logam bergantung pada keamatan sinaran

III elektron akan dikeluarkan serta merta dari logam sebaik sahaja sinaran mengenainya

IV tenaga kinetik maximum elektron yang dipancarkan adalah berkadar terus dengan keamatan sinaran

51. Apakah tujuan eksperimen michaelson-morley

A mengesan kewujudan corak belauan di atas cermin

B mengesan aras tenaga yang diskrit di dalam atom hydrogen

C membuktikan sifat kedualan zarah

D membuktikan kewujudan eter

By toh pek lan 82211/04

52. Which of the following statements are true?

I The second postulate for Einstein’s special theory of relativity is consistent with the negative result of the Michelson-Morley experiment which failed to detect the speed of the earth with respect to the hypothetical ether.

II The speed of light in vacuum is the same for all observers, dependent of the motion of the light source. (comment: this is an ill question lah, sort of an oximoron. “light in vacuum is the same for all observers” and “the speed of light is dependent of the motion of the light source” are two contradicting statements. One should avoid designing such question to avoid uncessary confusion.)

III Two event that are simultaneous in one reference frame are in general simultaneous in another frame which is moving with respect to the first.

IV Galilean transformation is inconsistency between EM and Newtonian view of absolute time , space, mass and energy.

53. Manakah antara berikut menyatakan spectrum garis ciri yang betul?

(comment: apa dia itu spectrum garis ciri? Adakah anda rujuk kpd specktrum daripada gas? Jika tak, apakah sebenarnya dia? Saya suspect anda cuba tanyakan soalan tentang garis ciri logam dalam proses penghasilan x-ray, betulke saya? Tapi, dalam syarahan saya ataupun nota tiada disentuh tentang garis -ciri dalam spektrum sinar-x logam. Maka, dengan alasan ini, sata syaki soalan anda ini di”kopi” sesuka-suka sahaja daripada buku-buku yang tertentu tanpa meninmbangkan samada adakah ia relevan dengan silibus kita ini atau tidak. Jadi nak “kopi” soalan pun sila guna kefahaman sikit lah…)

I Bergantung kepada tenaga kinetic electron yang hentam logam.

II Boleh diterangkan oleh teori gelombang

III Boleh diterangkan oleh teori foton

IV Bergantung kepada jenis logam sahaja

A. I,II B. I,II,III,IV C. I, II, III D. III.IV

E. Non of the above

54. Cahaya adalah sejenis gelombang electromagnet. Tetapi teori gelombang tidak dapat menerangkan suatu fenomena dinamakan kesan fotoelektrik.Oleh itu, terdapat beberapa perkara tidak dapat diterang oleh teori gelombang , iaitu :

I Tenaga kinetic maksimum fotoelektron tidak bergantung kepada keamatan cahaya.

II Tenaga kinetic maksimum fotoelektron tidak bergantung kepada frekuensi tetapi bergantung kepada panjang gelombang.

III Jika frekuensi cahaya kurang dari nilai tertentu ( frekuensi ambang ), tiada fotoelectron boleh dibebaskan walaupun keamatan cahaya sangat tinggi. Sebaliknya, bila frekuensi cahaya lebih daripada frekuensi ambang, fotoelektron akan dibebaskan walaupun keamatan cahaya sangat rendah.

IV Fotoelectron akan dibebaskan serta merta apabila fotoelectron memungut tenaga yang mencukupi untuk bebaskan diri dari permukaan logam.

(comment: jenis soalan itu adalah terlalu biasa dah. Kan you boleh reka soalan yang lebih canggih sikit?)

55. The maximum kinetic energy of the photoelectrons are depends

I light frequency

II work function

III light intensity

IV light energy

A II, III

B I, II, III

C I, II, IV

D I, III, IV

E Non of the above

(comment: jenis soalan itu adalah terlalu biasa dah. Kan you boleh reka soalan yang lebih canggih sikit?)

56. According to the de Broglie hypothesis, all the particle have same associated wavelength , so which particle has the smaller velocity ?

I proton II electron III neutron IV particle a

A I, III B II, IV C III D II

E Non of the above

(comment: jenis soalan itu adalah terlalu biasa dah. Kan you boleh reka soalan yang lebih canggih sikit? Kopiying disyaki.)

57. Which of the following statement(s) is(are) true to support light is to display wave-particle duality by experimental evidence ?

I it is described as a particle in the photoelectron effect

II it is described as a wave when the diffraction of electron from a crystalline surface

III it is described as a particle in phenomena such as atomic transitions and the photoelectric effect

IV it is described as a wave in phenomena such as interference and diffraction

A I, II

B II, III

C III, IV

D I, IV

E Non of the above

58. Which of the following statement(s) is(are) true to support electron is to display wave-particle duality by experimental evidence ?

I it is described as a particle in the photoelectron effect

II it is described as a wave in the diffraction of electron from a crystalline surface

III it is described as a particle in phenomena such as atomic transitions and the photoelectric effect

IV it is described as a wave in phenomena such as interference and diffraction

A I, II

B II, III

C III, IV

D I, IV

E Non of the above

Answer : B

(both questions aboth seems to be original to me)

59. Which of the following statement(s) is(are) true for the basic of the Bohr theory as it applies to an atom of hydrogen ?

I The electron moves in circular orbits about the atom under the influence of the Coulomb force of attraction.

II Only certain orbits are stable.

III Radiation is emitted by the atom when the electron jumps from a more energic initial stationary to a higher state.

IV The size of the allowed electron orbits is determined by an additional quantum condition imposed or the electron’s orbital angular momentum.

A I, II, III

B I, III, IV

C II, IV

D I, II

E Non of the above

By OOI YEE NING(82113)

60. In the Bohr model of the atom

a) Gravitational forces play a significant role.

b) Electrons do not radiate energy when they are in a stable orbit

c) The electrons spiral into the nucleus

d) The energy of an electron in a stable orbit is an integral multiple of h/(2p)

e) None of these is correct

(comment: this doesn’t sound as an original question to me)

61. The first Bohr radius, r_o is 0.0529nm and the corresponding energy, E_o, is 13.6eV.The wavelength of the light emitted as a hydrogen atom undergoes a transition from state n=3 to n=2 is

a) 656nm

b) 486nm

c) 434nm

d) 410nm

e) none of these is correct

(comment: this doesn’t sound as an original question to me)

62. Which one of the following statements is false?

a) The obits in the Bohr model have precise sizes, whereas in the quantum mechanical picture of the hydrogen atom they do not.

b) In the absence of external magnetic fields both the Bohr model and quantum mechanics predict the same total energy for the electron in the hydrogen atom.

c) The spin angular momentum of the electron plays a role in both the Bohr model and in the quantum mechanical picture of the hydrogen atom.

d) The magnitude of the orbital angular momentum cannot be zero in the Bohr model, but it can be zero in the quantum mechanical picture of the hydrogen atom.

(comment: this doesn’t sound as an original question to me)

63. According to the Bohr model, what determines the shortest wavelength in a given series of wavelengths emitted by the atom?

a. The quantum number n_i that identifies the higher energy level from which the electron falls into a lower energy level.

b. The quantum number n_f that identifies the lower energy level into which the electron falls from a higher energy level.

c. The ratio n_f /n_i, where n_f is the quantum number that identifies the lower energy level into which the electron falls and n_i is the quantum number that identifies the higher level from which the electron falls.

d. The sum n_f + n_i of two quantum numbers, where n_f identifies the lower energy level into which the electron falls and n_i identifies the higher level from which the electron falls.

e. The difference n_f - n_i of two quantum numbers, where n_f identifies the lower energy level into which the electron falls and n_i identifies the higher level from which the electron falls.

(sorry, I still suspect that this is not an original question. Please correct me if I am wrong)

By YENG TIAN LOON ( 82794 )

64. A phase shift of 180°occurs when the light wave

a) Is transmitted through a boundary surface into a medium that is more dense than the medium from which the wave came.

b) Is transmitted through a boundary surface into a medium that is less dense than the medium from which the wave came.

c) Reflects from the boundary surface of a medium that is less dense than the medium in which the wave is traveling.

d) Reflects from the boundary surface of a medium that is more dense than the medium in which the wave traveling.

e) Both c and d are correct.

(This is obviously a copied question as we never mention about such kind of concept througout the course, neither in the lecture nor in the lecture notes. So I suspect this to be a question copied from elsewher. Correct me if I am wrong. But I am not going to believe you unless you convince me other wise. If u want to copy also please copy wisely lah my dear friend.)

65. The wave function for a particle in a one-dimensional box of length L

a) Is constrained by the boundary conditions y(0)=0 and y(L)=0.

b) Must be zero everywhere outside of the box.

c) Is given by y(x)=Asinkx, where A is a constant. (comment: this statement is not generally correct as the form of the solution depends on the choice of origin in the well.)

d) Restricts the possible energy of the particle to E=U²K²/(2m). (what the heck is U?)

e) All of these are correct.

By LIM SEANG CHIN (82445)

66. In the emission of photoelectric by a given mental when the wavelength of the light incident is increase,

a) the average kinetic energy of the emitted electron increase.

b) The maximum kinetic energy of the emitted electron increase.

c) The minimum kinetic energy of the emitted electron decreases.

d) The minimum kinetic of the emitted electron increase.

e) The average kinetic energy of the emitted electron decrease.

f) (almost pengsan when reading your question. Its so grammatically very ill lah. Your question should be like this: “When the incident light irradiated on a given mental surface is increased in the wavelenght”. In any case, the question is just too boring and lack of originality.)

By NAME: NURRUL ANISAH BT ISMAIL; MATRIC NO: 82608/04

67. The electron in hydrogen atoms has made a transition from its energy level E2 to energy level E1 and emits a photon. The wavelength of the photon is given as

a)      h/E2-E1

b)      hc/E2-E1

c)      E2-E1/h

d)      E2-E1/hc

68. The following statements about Bohr’s postulate are true EXCEPT

a)      Electron is losing energy while orbiting around a nucleus.

b)      Electron can change its orbit by radiation of energy.

c)      Electron can orbit around the nucleus in certain orbit without emission of energy.

d)      Electron is allowed to move in orbit which has angular momentum multiple of h/2.

(Sounds not copying from elsewhere but they are too simple.)

Prepared by Nor Aini Suhaidan， 71588/02

69. Which of the following statement(s) is (are) true about photon?
    
    

A) photons that are absorbed by atoms in the target in PE effect shall eject photoelectrons immediately
B)the energy of the single photon is given by E=hv
C)a photon can also materialized into an electron and a positron
D)kinetic energy of electron is transfered to energy of photons (comment: this last statement is meaningless because it does not specifically refer to any process.)

70. Which of the following statements is (are) true about Einstein's PE theory?
    
    a)light has momentum

b)hn and W_o depend on the radiation intensity
c)the energy of the photons is in concentrated bundles
d)there is a time lag in the PE effect (this statement is not precise enough to make it a sensible one.)

By MAZIDAH BINTI ISMAIL, 72237/02

71. Which is/are true about Bohr model of atom?

i. It does not work for atom with more than one electron

ii. In Bohr theory the angular’s momentum is quantized.

iii. It cannot predict the relative intensities of the photon radiation from atoms.

iv. Bohr’s model is based on Thompson’s model

A. i , ii

B. ii

C. i ii iii

D. i, ii, iii, iv

E. none of above

72. Predict the value of the quantum number for a dust particle which mass is 5 x 10^-6g and speed of 2 x 10^-6 that is confined to be in a box size 0.05m

A. 1.023 x 10²³

^B. 1.023 x 10^-23

C. 1.509 x 10^-23

D. 1.509 x 10²³

E. none of above

(this seems to be not an original question to me)

BY Chew Siau Huey    79060/04

73. Antara kes yang berikut, yang manakah akan menyebabkan voltan penghenti berubah? (u kena menyatakan dengan spesifik proses apa yang sedang dirujuk. Jika tidak siapa yang tahu voltan penghenti yang terlibat?)

i. bahan yang sama dan disinari oleh cahaya yang mempunyai keamatan cahaya yang berbeza.

ii. bahan yang sama dan disinari oleh cahaya yang mempunyai keamatan cahaya yang sama

tapi frekuensi cahaya yang berbeza.

iii. bahan yang berlainan tapi disinari oleh cahaya yang mempunyai keamatan dan frekuensi yang sama.

iv. bahan yang berlainan tapi disinari oleh cahaya yang mempunyai keamatan cahaya yang 

sama tapi frekuensi cahaya yang berbeza.

(looks like quite original but the phrasing of the question requires some touching up to make it sound clearer and gramatically-free)

By Cik Maisarah Hussain (68269/02), Hasniyah Sulaiman (68295/02)

74. Which of the following statement is (are) true about Davisson and Gremer (DG) experiment?

I. DG fails to confirm the wave nature of electron

II. DG confirm the wave nature of electron

III. The electron in the DG experiment is accelerated to K= 54 eV (comment: this is not a good question to ask. This is a physics course not a history course. The figure “54 eV or 54 keV” does not really matter here. What really important about that experiment is the observation of diffraction pattern by electron.))

IV. Electron do behave like particle as postulated by de Broglie

A. I, II B. II, III C. I, IV D. IV

75. Which of this statement is (are) not correct?

I. The smallest orbit or hydrogen, the Bohr’s radius; r₀ = 4πЄ₀²/m_ee²

II. If the change of energy is positive, the energy must be absorbed (comment: you got to define the statement more precisely than here, e.g. “ if the change of the energy of an atom in an process is +ve that would mean energy are absorbed by the atom. Such a statement would un-ambiguously make the statement a true one.)

III. Electron at high n is not tightly bounded to the nucleus by the EM

force

IV. When an excited electron in the atom falls back to the lower energy states (de-excited), EM wave is absorbed

A. I, II B. II, III C. II, IV D. II, III, IV

Answer: C

76. Dalam tahun 1905, Einstein memajukan mekanisme yang menyebabkan berlakunya kesan fotoelektrik. Antara berikut, pernyataan manakah benar?

A. Beliau menganggap tenaga yang dikeluarkan oleh sebarang pengayun adalan dalam bentuk kuantum.

B. Apabila nilai frekuensi melebihi frekuensi ambang, keamatan cahaya akan berkurang menyebabkan jumlah kuanta cahaya bertambah.

C. Elektron yang dikeluarkan akan bertambah jika nilai frekuensi kurang daripada frekuensi ambang.

D. Nilai frekuensi ambang bergantung kepada keamatan sinaran dan tidak bergantung kepada jenis logam.

77. Antara berikut yang manakah pernyataan benar mengenai spektrum atom hidrogen?

V. Garis-garis spektrum kelihatan semakin jauh antara satu sama lain apabila panjang gelombangnya semakin pendek.

VI. Di dalam kawasan ultraungu, siri Lyman yang mengandungi garis-garis spektrum telah ditemui.

VII. Panjang gelombang minimum bagi spectrum atom dalam siri Balmer ialah 3.65x10^-7 m

VIII. Siri Brackett melibatkan peralihan elektron daripada orbit-orbit yang lebih tinggi kepada orbit n=3

A. I, II, III B. II, III C. I, II D. II, III, IV E. I, III

78. Pernyataan manakah adalah benar?

IX. Dalam proses Compton, sinar elektromagnet diserakkan dengan sudut θ dan sebahagian daripada tenaganya digunakan untuk membebaskan elektron. (comment: “membebaskan elektron” sounds not really right here as by definition the process is happening between photon and free electron. So the problem of “memmbebaskan elektron” should not be of any relevance here. To make this statement a better one, maybe you should find an alternative description to the word “membebaskan” to avoid unecessary confusion.)

X. Dalam proses fotoelektrik, foton akan memindahkan seluruh tenaganya untuk membebaskan elektron dari ikatan atom. (sounds like copying from my past year question)

XI. Tenaga kinetik maksimum elektron yang dipancarkan berkadar terus dengan keamatan sinaran dan bukannya frekuensi sinaran (Hey, what process are you talking about here? PE or Compton? Whithout this made clear this statement makes no sense.)

XII. Dalam proses serakan Compton, tenaga foton yang terserak akan berkurang dengan bertambahnya sudut serakan foton dan mencapai nilai minimum apabila φ=180°

By ZURAINY BINTI MD NAYI, MATRIC NO: 82244

79. “toms can only absorb light energy in discrete ‘energy packets’ or quanta, this quantum of light energy is called photon. Who actually made this statement?

a)      Maxwell

b)      Galilean

c)      Einstein

d)      Planck

(this is not a good question to ask in a physics course else it would be like a history course. We should ask more physics-relavent question instead of memorising history.)

By Teh Kheng Hock 82737, Wong Chee Hong 82227 (Due to time limitation I have not carefully checked thru the questions posted below. But I think they are quthentic and original)

80. In an interstellar space pod race, two space pods we leading the chasing pack by some distance. It is without a doubt that either one of them would be the victor. As they near the finishing line, space pod A, piloted by Alex Yoong, is leading, with only 500 m from the finish line, with a speed of 0.87c. Following close behind is space pod B, piloted by Karamjit Singh, 600 m from the finishing line, with the speed of 0.92c. Time seemed to be at a stand still as fans hold their breath to see who crosses the finishing line first. Assume that the two space pods’ speeds are constant till the end, which space pod will prove the winner?

A. Space Pod A in relativistic view, Space Pod B in classical view;

B. Space Pod B in relativistic view, Space Pod A in classical view;

C. Space Pod A in relativistic view, Space Pod A in classical view;

D. Space Pod B in relativistic view, Space Pod B in classical view;

E. Both of them cross the finishing line together.

81. Which of the following statements is(are) TRUE?

I. If one is able to fly, near the speed of light, in the opposite direction of the

earth’s rotation, according to time dilation, he should be able to travel back in

time.

II. Likewise, if one flies near the speed of light, along the earth’s rotation, he or

she should be able to travel to the future.

III. The rest mass of an object is always smaller than its relativistic mass.

IV. The relativistic mass of an object depends on its speed and time only.

A.I and II

B.III only

C.III and IV

D.I, II and III

E. None of the above.

82. It is impossible to achieve a velocity which exceeds the speed of light because:

I. As the object approaches the speed of light, c, it’s length would contract. If it

reaches c, the object would thus have no length at all.

II.As the object approaches the speed of light, its mass would increase; thus, if it

reaches c, the object would have infinite mass, which is impossible.

III. To reach the speed of light, much energy is needed, and subsequently, to reach

the speed of light, infinite energy is needed, something of which, is impossible.

IV. According to the time dilation effect, it will take infinite time to obtain or go

over the speed of light.

A. I and II

B. I , II and III

C. III only

D. I, II, III and IV

E. None of the above

83. Which of the following statements is(are) true?

I. The laws of quantum mechanics are only valid in the atomic domain

II. The laws of classical physics are only valid in the classical domain

III. The laws of quantum mechanics are valid in a domain where atomic and

classical domains overlap.

IV. The laws of classical physics are valid in a domain where atomic and classical

domains overlap.

A. I and II

B. III and IV

C. I, II, III and IV

D. I, II and III

E. None of the above.

Our answers to the above questions would be :

80. B

Because, whoever who needed the shortest time to reach the finishing line would definitely finish first.. s=vt, t=s/v.With classical calculations, A’s time would be shorter. However, in relativistic view, the distance is shortened by the lorentz factor. I assumed the speed, v, to be constant at both views..

I hope you understand what I mean, sir..

I also seriously do not know if my question is correct at all.. am just trying, albeit too late..

81. B.

The first and second statement, We recall from somewhere, is false.. The third is obviously true, while the last is false because relativistic mass doesn’t depend on time..

82.B

I came up with this question remembering the tutorial session you had with us :D kinda un-authentic.. I apologize for that....

83 B

The options 3 and 4 are obviously correct, the first and second are only partially correct, as the word ‘only’ made them invalid..

By 1.FURQAN AULIA (67454/01), 2. FAUZANA AHMAD DZIAUDDIN (66978/01), 3. MARLIANA MOHAMED AKHIR / (66994/01)

84. which statment(s) is (are) true?
    i.Energy carried at speed of group wave
       ii.Energy carried by a particle is continuum and given by E2 = m02c4 + p2c2
      iii. Energy carried by a wave is corpuscular and represent the only made of interaction between two points.
      iv. Wave and particles represent the only modes of energy transport between two points

85. An electron is accelerated through a potential,V. The velocity of the electron is:
    
     A. Indirect propotion with v for small v value and (v)1/2  for large v value
     B. Indirect propotion with (v)1/2 for small v value and constant for large v value
     C. Indirect propotion with (v)1/2 for small v value and v for large value
     D. Indirect propotion with v for small v value and constant for large v value
     E. Indirect propotion with (v)1/2
    (the problem here is: what do u mean by “indirectly proportional”? do u mean inversely proportinal?)                      

86. Which statment(s) is (are) true regarding to the planet's assumption about the nature of the ascilators in the cavity walls? (Planet’ assumption in the cavity wall? I dunt really understant the question y try to ask lah. Did we ever mention planet’s assumption in BB radiation?)
    
     A. Standing wave modes is assumped to be propotional to kT,based on the theorem of equiportition of energy.
     B. Oscillators emitted or absorb energy when making a transition from quantum state to another.
     C. Energy of an oscillator can have only certain discrete values.
     D. The effectivness of oscillators in the cavity walls depend salely on the temperature.
    
    
    
87. Which one of these statments is (are) true about the changes that happens when IR wave converts to X-Ray in the spectrum of electromagnetic?
    
     A. Frequency increases,Wave length increases and Energy per photon increases.
     B. Frequency decreases,Wave length increases and Energy per photon decreases.
     C. Frequency increases,Wave length decreases and Energy per photon increases.
     D. Frequency decreases,Wave length decreases and Energy per photon decreases.
     E. Frequency increases,Wave length decreases and Energy per photon decreases.
    
    

comment: this question seems to be too canggih lah. In fizik we dunt really know how to ‘convert’ an IR to a X-ray. So may be you should rephrase you question by saying: “what are the difference between the energies and wavelenght of an IR compered with a x-ray? Then you got to rephrase your option too so that they are consistent with the way the question is posed”. In short this question is illy phrase but could be made sensible if it corrected properly.

By Tan Hooi Sin, 79295/04

88. A photon of frequency, f is scattered by on electron initially at rest. What is the maximum kinetic energy of the recoil electron?

1. hc/l(1+ 2hf/moc²)
2. hc/l[(2h/ moc ) (2h/moc- l)^-1]
3. 2hc/(2hl+ mocl²)
4. 2h²f ²/ moc²(1+2hf/ moc²)

Ans: D

89. The relative probabilities of three experiments ( I, II, III ) as functions of energy in Carbon is shown below. Which of the statements below is true about ( I, II and III )?

	I	II	III
A	Photoelectric Effect	Compton Scattering	Pair Annihilation
B	Photoelectric Effect	Compton Scattering	Pair Production
C	Pair Annihilation	Photoelectric Effect	Compton Scattering
D	Pair Production	Compton Scattering	Photoelectric Effect

1. Which is the phase velocity of the de Broglie waves of a particle of rest mass mo and the de Broglie wavelength, l?

1. c² [ 1 – (moc l/h) ²]
2. c³ [ 1 + (moc l/h) ²]
3. c Ö[ 1 + (moc l/h) ²]
4. c²Ö[ 1 + (moc l/h) ²

By WAN NORSURYANI BT WAN NASRU, MATRIC NO:82221/4 (comment: I will take these questions as not original.)

90. When a monochromatic light is incident with a metal plate of vacuum tube,

photoelectrons are produced. If another light of larger wavelength is used,

a)      The average kinetic energy of photoelectrons emitted decreases.

b)      The average kinetic energy of photoelectrons emitted increases.

c)      The kinetic energy of photoelectrons emitted remains unchanged.

d)      The average kinetic energy of photoelectrons emitted has the minimum value.

91. Pauli’s exclusive principle is always obeyed by (comment: come on lah, you want to copy also please copy wisely, not until to the point to simply copy without knowing that the question u copied is not in our zct 104 syllybus))

a)      All atoms.

b)      All charged atoms.

c)      All atoms with spin number ½.

d)      All atoms with one electron.

By Yam Ing Yee (74150/03), Tan Sze Nee (74121/03) (I think these questions are very original despite some defects. Good to u all.)

92. Which statement is true ?

a. All the Theory Classical Physics can be used straight away in the Physics modern . (it’s a good statement to ask but maybe the wording needs to be rephrase a bit)

b. Galilean Transformation can be used successfully in the field of electric and magnetic. (maybe u should say: “We can always apply GT to the Maxwell theory of light”. However, such a statement is not of much significant or make much sense. GT can be “always successfully” applied to any theory or any laws of physics, irrespective of whether the outcome of the application is consistent with established fact or not.)

c. We have to change Lorentz Transformation to Galilean Transformation at high velocity. (The phrasing is a bit not right. Maybe u should say: “when the velocity is involved is approaching to that of the speed of light in free space c, we have to supplant Galilean transformation with that of Lorentz”)

d. Classical EM theory is inconsistent with Galilean Transformation.

93. Which Statement is wrong ?

a. There are no interactions between particle and wave. (this is not a good question to ask lah. Its too general.)

b. Energy can be carried by through particle and wave. (comment: energy can be carried in the form of particle or in the form of wave.)

c. According de-Broglie , electron can become wave and particle simultaneously. (de Broglie says electron should also has wave property. However, when one says “electron can become wave and particle simultaneously” then this is a difficult statement to say yes because the wave and particle nature cannot show up simultaneously. Its kind of too philosophical to be a good physics question in an objective form.)

d. The photon carries energy is in contrast to the way wave carries energy . (sounds ok to me)

94. Which statement is True ?

a. When the light is incident on certain metallic surface , electrons can be emitted from the surface is called black body radiation. (wow! This really sounds ‘original’. It’s a good question to trap those who are confused between different physical processes.)

b. The maximum Kinetic energy of the photoelectrons increase when the light frequency increase .

c. According to the Planck’s Hypothesis, as the intensity of the radiation-emitting black body decrease ,the temperature will increase. (obviously this is a false statement)

d. Electrons will be emitted if the incident light frequency falls below cutoff frequency.

Prepaired by: Ching Chin Guan, Metric number: 81838 (ok)

95. Steve had invented a car which back to the past time. It has a speed of 99% of lightspeed in order to make it back to past time. The dimension of the car is 2.00m height and 5.00m length. When Steve drive the car what is the dimension of the car relative to Steve? (comment: of course steve will never make it to the past at this speed of only 99% c.)

A)0.71m heght & 2.00m width B)5.00m height & 0.28m width

C) 0.71m height & 0.28 width D) 4.50m height & 2.87m width

E) The dimension of the car did not change

Ans: E

96. In photoelectricity effect, the kinetic energy to eject electron is K=hυ – W, W is the work required to

i ) cater for the loses of kinetic energy due to internal collision of the electron .

ii ) radiate photon from the atom

iii ) eject all the electron in the atom

iv ) overcome the attraction from the atom in the surface.

Chose which of the following combination below is TRUE.

A) i, ii, iii, iv B) i, iv C) ii, iv D)ii, iii, iv

E) None of the above

97. Which of the law below must be obeyed by the pair production?

I. Charge conservation, total linear momentum, total relativistic energy are to be obeyed in the process.

II. Pair production must not occur in empty space.

III. Pair production must occurs in proximity of a nucleus.

IV. Pair production must occurs when two particle collides witheach other.

A) i, ii, ii, iv B) i,ii, iv C)i, ii, iii D)ii, iii, iv

E) None of the above

By EU HAN PEEU (81855/04) (these questions sounds too ordinary and not original)

98. Two distant spaceships are receding from earth at 0.70c, in opposite directions. How fast does an observer in one spaceship measure the other to be moving?
99. A TV tubes accelerated electrons from rest though a potential difference of 65kV. Find their final speed?
100. Calculate the momentum for an electron 2MeV.
101. For an X-ray tube with an iron target to produce the Lα line, what is the approximate minimum accelerating voltage for it?

Soalan-soalan ini disediakan oleh:-Sim Chong Keat (82668/04), Teoh Chong Yew (82750/04) (Sounds like very very standard exam questions lah. I don’t really see much originality here. Furthermore, I need questions in objective form, not structured form.)

102. Apakah yang dimaksudkan dengan pemalar planck? (comment: sukar nak jawab soalan ni…)
103. (a) Lukiskan satu gambarajah berlabel untuk menunjukkan ciri-ciri asas suatu

susunan ujikaji yang digunakan untuk mengkaji kesan fotoelektrik.

(b) (i) Jelaskan bagaimana anda menggunakan susunan ujikaji itu untuk

menentukan frekuensi ambang suatu logam?

(ii)Lakar pada paksi yang sama,graf bagi keputusan yang mungkin anda

dapati bagi dua logam yang berlainan dalam ujikaji yang serupa dan huraikan,

dengan memberi sebab-sebab, keserupaan dan perbezaan bentuk graf-graf itu.

104. .Dalam suatu eksperimen pemancaran fotoelektrik,permukaan suatu logam di

dalam satu tiub vakum disinari dengan cahaya monokromatik.Jika eksperimen ini

diulangi dengan cahaya yang sama panjang gelombang tetapi dengan keamatan

dua kali keamatan asal ,bagaimana ini akan mempengaruhi

(a) tenaga foton,

(b) tenaga kinetic maksimum fotoelektron,

(c) fungsi kerja logam itu,

(d) arus foto?

105. “Terangkan pengujaan pertama bagi atom hidrogen ialah 10.2eV” .Terangkan

apakah yang dimaksudkan oleh pernyataan ini.Hitungkan laju minimum electron

yang boleh mengujakan satu atom hydrogen.

106. Apabila sinaran-X dengan panjang gelombang 100pm ditujukan pada satu hablur yang tertentu,sudut tuju paling besar di mana pantulan Bragg boleh didapati ialah 60 darjah.Apabila sinar-X dengan panjang gelombang λ’ ditujukan pada hablur yang sama,sudut tuju paling besar di mana pantulan Bragg boleh didapati ialah 25 darjah .Kirakan λ’. (181pm)

107. Suatu foton mempunyai panjang gelombang 500nm.Hitungkan momentum foton itu?

108. Tuliskan hubungan antara panjang gelombang electron,λ dan momentum electron,p.Kirakan beza keupayaan pemecut yang diperlukan supaya electron-elektron yang bermula dari pegun mempunyai panjang gelombang 0.145nm.

109. Dapatkan satu hubungan bagi panjang gelombang de Broglie satu electron dalam sebutan tenaga kinetiknya E,jisim electron m dan pemalar Planck h.

110. Jika satu electron dipecutkan dari pegun melalui beza keupayaan 100V, berapakah panjang gelombang bagi electron itu?

111. Jarak pemisahan satah-satah atom satu hablur ialah 0.300nm.berapakah bilangan tertib belauan yang boleh didapati jika sinar-X monokromatik yang mempunyai panjang gelombang 0.154nm ditujukan pada hablur itu?

112. Terangkan mengapa tiada belauan sinar-X boleh didapati dengan hablur ini jika panjang gelombang sinar-X yang digunakan melebihi suatu nilai yang tertentu dan kirakan nilai itu. (0.60nm)

Questioned by :LOW BOON HOOI (82461/04) (Sounds like the questions are designed based on the notes. Nevertherless this is better than copy bulat-bulat from existing questions bank.)

113. Which of the following is correctly described about Lorentz Transformation?

Ⅰ All inertial frames are equivalent

Ⅱ All physical processes analyzed in one frame can also be analyzed in order inertial frame and yield consistent result

Ⅲ A transformation law is required to related the space and time coordinates from one frame to another

Ⅳ The length is independent of the state of motion. So is the flowing rate of time

114. which statement(s) is(are) true about matter(particles)?

Ⅰ A particle is discrete or corpuscular in nature

Ⅱ A particle can’t be localized completely

Ⅲ A particle has mass

Ⅳ A particle is electrically charge

115. Which of the following describe the Plank’s assumption correctly?

Ⅰ The energy of an oscillator can have only certain discrete values,E=h/mc

Ⅱ The energy is quantized

Ⅲ Each discrete energy value corresponds to the same quantum state

Ⅳ The energies of oscillators in the cavity must assume a continuous distribution

116. The following statements are the process of photoelectric effect. Arrange them into the correct order.

Ⅰ Photoelectrons are ejected from the metal

Ⅱ The photoelectrons are attracted to the collecting anode by potential

different applied to the anode.

Ⅲ The photoelectrons are detected as electric current by the external

circuits

Ⅳ a metal surface is heated by the radiation of sufficient frequency, f

117. Which of the following correctly describe about x-ray production?

Ⅰ X-ray is produced when the metal surface is heated

Ⅱ X-ray is produced when the electrons in the vacuum cathode-ray is

accelerated by an electric field n impacted on the end of the tube

Ⅲ Part of the kinetic energy of the moving electron is converted into a x-ray

Ⅳ It involve the much higher energy scale

By Name:Goh Kee Kuang, Metric number:82342 (nothing special lah. I am expecting more creative kind of questions than these. For question 3, if this were designed by u yourself (but is not copy almost bulat-bulat from somewhere) than it’s a good question. I wish you are good.)

118. Which of the colored lights on a Christmas tree emits photons with the least energy?

(a) orange

(b)yellow

(c)violet

(d)ultraviolet

119. What is photoelectric effect?

(a) Emission of electrons from a hot metal surface when the metal radiated by photons.

(b) Emission of electrons from a cold metal surface when the metal radiated by photons.

(c) Emission of photons from a hot metal surface when the metal radiated by electrons.

(d) Emission of photons from a cold metal surface when the metal radiated by electrons.

120. A cruiser approach an aliens spacecraft at a velocity of 0.800c relative to the spacecraft.The cruiser’s captain fires an atomic ions at velocity of 0.950c relative to the cruiser.At what velocity do the aliens see the ions moves away from the cruiser?

(a) 0.150c

(b) 0.994c

(c) 0.194c

(d) 0.085c

By Teh Heng Ti, Metric Number : 82735

121. The confirmation of de Broglie’s suggestion that particle of matter should exhibit wave like behavior came in 1927 from experiments by Clinton J. Davidson and Lester H. Germer.

In the experiments, Davidson and Germer :

a) Directed a beam of electrons onto a crystal an a diffraction behavior was observed.

b) Directed a beam of x-rays onto a crystal and a diffraction behavior was observed.

c) Performed Young’s double-slits experiment with electrons and wave interference illustrated.

d) Strikes an electron with x-ray photon.

122. Only massless particle can travel at the speed of light. Which of the following particle travel at the speed of light?

1. Gluon
2. Photon
3. Graviton
4. Muon

a) 1 and 3

b) 2 only

c) 1 , 2 and 3

d) 2 and 4

e) None of above

Answer : c . Muon has mass of 105.7 MeV/c^2.Others have no mass.

123. A black body object was heated at 2000K and blackbody radiation emitted. The black body was then heated at temperatures 3000K and then 4000K. Which of the following statement is/are true about black body.

1. The amount/intensity of radiation emitted increase with increasing temperature.

2. The wavelength of the radiation emitted at 4000K is bigger than wavelength emitted at 3000K.

3. The wavelength at which highest intensity of the radiation are all same at 2000K , 3000K and 4000K because emit from the same black body system.

4. The total power emitted from the radiation proportional is to T^2 ; T= temperature.

a) 1 , 2 and 4

b) 1 only

c) 2 , 3 and 4

d) 1 and 4

e) none of above

Answer : b.

2)radiation wavelength at 4000K smaller then at 3000K.

3)wavelength at 4000K < 3000K < 2000K.

4)total power proportional to T^4

124. Which of the following statement is/are true about the Plum-pudding model.

1. An atom consists of Z electrons is embledded in a cloud of positive charges that exactly neutralize that of the electrons.
2. The positive cloud is heavy and comprising most of the atom’s mass.
3. Inside a stable atom the electrons sit at their respective equilibrium positive where the attraction of the positive cloud on the electrons balances the electron’ mutual repulsions.
4. All of the above are true.

125. A set of apparatus as below with light source from a lamp with low pressure gas. A spectrum will be produced after the light pass through the diffraction grating. The apparatus is then replaced with a light bulb. Which of the following statement is/are true?

1. A line spectrum will be produced by the light bulb.
2. A line spectrum will be produced by the lamp with low pressure gas.
3. A continuous spectrum will be produced by the light bulb.
4. A continuous spectrum will be produced by the lamp with low pressure gas.

Answer : 2 and 3 are true.

126. A electron produced diffraction pattern if it pass through a slit but this doesn’t happen to a human who pass through a slit. Why ? Becouse diffraction only happen to microscopic partical? (Comment: first of all, u cant pass thru a slit unless via the quantum tunnelling effect which is highly negligible in probability. Secondly, even if u pass through the slit too u wont see the diffraction pattern bcos the wave nature of a mactroscoplic “particle” like u is too tiny to be physically detectable..)

By Name: Joanna Tan Choay Ee, Matric No. : 82379/04

127. Which of the following statement(s) is/ are true?

I. When an electron makes transition from the highest level to the lowest level, the longest wavelength is emitted.

II. Transition from lower energy levels to higher levels is known as absorption.

III. Bohr made an assumption that the angular momentum of the electron is quantized.

IV. Ernest Rutherford is the person who provided the first model of the atom that predicted the discrete wavelengths emitted by atomic hydrogen.

A. I, II B. II, III C. II, III, IV D. II, IV E. None of the above

(Ans: B) I – wrong because should be the shortest wavelength emitted.

IV- wrong because not Ernest Rutherford, should be Niels Bohr

128. Which of the following statement(s) is/are true?

I. X-ray can be produced when electrons accelerated through a large potential difference and collide with a metal target.

II. The cut-off wavelength λο is not independent of the target metal.

III. Bremsstrahlung X-ray are emitted when the electrons decelerate.

IV. X-rays are electromagnetic waves.

A. I, II B. I, III C. I, II, IV D. I, III, IV E. None of the above

(Ans: D) II- wrong because the cut off wavelength is independent of the target metal.

129. Which of the following statement(s) is/ are the important features for stimulated emission?

I. Two photons go in and one photon comes out

II. One photon goes in and two photons come out

III. The two electromagnetic waves are coherent

IV. The emitted photon travels in the opposite direction as the coming photon

A. I, III B. II, III C. I, III, IV D. II, III, IV E. None of the above

(Ans: B) IV- wrong because they travel in the same directions

(Despite not in the syllybus of zct 104 and being suspected a copycat, the ‘designer’ of the question claimned it to be original.)

130. Which of the following statement(s) is/ are true?

I. The Bohr radius = 0.53A which is equal to 5.3x10ˉ¹³m

II. The Frank-Hertz experiment shows the excitation of the atoms to discrete energy levels

III. The laws of quantum physics and the laws of classical physics do not give the same result (generally this is not a true statement. In the special case where the principle quantum number n is large both thoery gives similar prediction.)

IV. Classical EM predicts that an electron in a circular motion will radiate EM wave at the same frequency.

A. II, IV B. II, III , IV C. I, II, III, IV D. I, II, IV E. None of the above

(Ans: D) III – wrong because both laws will give the same result

131. Which of the following statement(s) is/ are true?

I. Line spectrum is a series of discrete electromagnetic wavelengths emitted by the atoms of a high-pressure gas that is subjected to a sufficiently low potential difference.

II. The line spectrum of atomic hydrogen starts with the Balmer series. (this is an ill question to be asked. What do u mean by “start”? u got to be more specific here.)

III. According to quantum mechanics, an electron does not reside in a circular orbit.

IV. In a normal room temperature, most of the electrons in atoms are found in E=0.

A.I,II B. I, III C. III, IV D. I, III, IV E. None of the above

(Ans: E) I- wrong, should be low-pressure gas… high potential difference

II – wrong, should be start with Lyman series (its not very correct to say that ‘The spectrum starts with Lyman series unless u make the statement more precisely by referring to the length of the wavelengths)

IV- wrong, E is not equal to zero.

So only III is correct.

132. Which of the following statement(s) is / are corrent?

I. A photon in a vaccum always travels at the speed v<<c

II. A photon in a vaccum do has mass.

III. Only light with a frequency equal to a certain minumum value of fο will eject electron.

IV. An electron situated at the outside of the metal with the minimum energy will has the kinetic energy as well.

A. I, II B. II, III C. II, IV D. II, III, IV E. None of the above

(Ans: E)I – wrong, suppose to be at the speed, v=c

II – wrong, because photon does not have mass in vaccum

III – wrong, suppose to be frequency equal to or more than

IV – wrong, because at the outside of the metal, the electron does not have kinetic energy

By Lim Hong Heng ,81929/04, Aw Gen San,81809/04

133. The purpose to solve the Shrodinger equation are:

1. To predict e.g. the position of the object m as a function of time.
2. The potential V(x) represent the environment influence on the particle.
3. To find out the wave function forms nodes at boundaries.
4. To obtain essential physical information of the particle which is subjected to the influence of the external potential V(x).

A. i, ii B. iii C. ii, iii, iv D iii, iv E. none from

above (ANS: A)

134. The reason of tunneling phenomena can happen are

1. Itfs due to the continuity requirement of the wave function at the boundaries when solving the TISE
2. The wave function cannot jus gdie offff suddenly at the boundaries of a finite potential well
3. The wave function cannot diminishes in an exponential manner which allow the wave function to extent slightly beyond the boundaries.
4. The quantum tunneling effect is a of the wave nature of particle,which is turn governed by the TISE.

A. i, iii B. iii C. ii, iii, iv D i,ii, iv E. none from

above (ANS: D)

135. Which of the following are Bohr postulate?

1. Coulombfs attraction is equal to centripetal force.
2. n de Broglie wavelength must fit into the circumference of an orbit.
3. An electron moving in such an allowed orbit to radiate EM energy
4. The angular momentum of the orbiting electron is not quantized.

A. i, iii B. iii C. ii, iii, iv D i,ii E. none from

above (ANS: D)

136. Which of the following statement(s) is(are) true?

I. Plum-pudding model fails to explain the emission and absorption line spectrum from atoms because it predicts only a single emission frequency

v = (1/2ƒÎ)ã(k/m)

II. Plum-pudding model serves as a prototype to the next model which is built on the

experience gained from this model

III. The Rutherford model succeed to explain the pattern of discrete spectral lines.

IV. Plum-pudding model fails to explain the back-scattering of alpha particle seen in Rutherfordfs scattering experiment

A. I,III B. I,II,IV C. II,III,IV D. I,II,III,IV E. none from above

(ANS: B)

By Ag Heng ,81929/04, Aw Gen San,81809/04 (hm…sounds like u have gone through the notes and have designed quite original questions based on them. Its good.)

137. The purpose to solve the Shrodinger equation are:

1. To predict e.g. the position of the object m as a function of time.
2. The potential V(x) represent the environment influence on the particle.
3. To find out the wave function forms nodes at boundaries.
4. To obtain essential physical information of the particle which is subjected to the influence of the external potential V(x).

A. i, ii B. iii C. ii, iii, iv D iii, iv E. none from

above (ANS: A)

138. The reason of tunneling phenomena can happen are

1. Its due to the continuity requirement of the wave function at the boundaries when solving the TISE
2. The wave function cannot just die off suddenly at the boundaries of a finite potential well
3. The wave function cannot diminishes in an exponential manner which allow the wave function to extent slightly beyond the boundaries.
4. The quantum tunneling effect is a of the wave nature of particle,which is turn governed by the TISE.

A. i, iii B. iii C. ii, iii, iv D i,ii, iv E. none from

139. Which of the following are Bohr postulate?

1. Coulomb’s attraction is equal to centripetal force.
2. The de Broglie wavelength must fit into the circumference of an orbit.
3. An electron moving in such an allowed orbit to radiate EM energy
4. The angular momentum of the orbiting electron is not quantized.

A. i, iii B. iii C. ii, iii, iv D i,ii E. none from

140. Which of the following statement(s) is(are) true?

I. Plum-pudding model fails to explain the emission and absorption line spectrum from atoms because it predicts only a single emission frequency

II. Plum-pudding model serves as a prototype to the next model which is built on the experience gained from this model

III. The Rutherford model succeed to explain the pattern of discrete spectral lines.

IV. Plum-pudding model fails to explain the back-scattering of alpha particle seen in Rutherfordfs scattering experiment

A. I,III B. I,II,IV C. II,III,IV D. I,II,III,IV E. none from above

By Peter Neoh Soon Leong 82634/04 (if this is originally from I think it’s a good question)

141. Consider that during a seminar,a wireless michrophone is being used by the resenter.Suddenly,there is some of some kind of sound distraction happen.

1. What theories best describes the phenomenon??

a. Pair pruduction and annihilation

b. de Broglie wave duality

c. Wave aspects of material particles

d. Super imposition of waves

142. Explain the phenomenon by using the theory.

By: CHONG LAI SOON  79067/04, WANG YUIIK LUNG  79319/04

143. Imagine a bicycle wheel with radius, r is circulating with some velocity, v. What is the radius of the wheel when the velocity, v is reaching the speed of light, c?

A) r B) 2r C) 1/2 r D) 3/4 r E) none of above

Answer: A ( i think is A gua because the angular velocity is perpendicular with the direction of the motion. So, please correct me if im wrong lorrr. thank you ar.) (comment: I think I agree with u gua…)