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*Mudra* Physical Sciences For NET & SET Exams. Of UGC-CSIR _____________________________________________________________________________ (MCQs) Part B & C Vol-06 0 MUDRA PHYSICAL SCIENCES VOLUME-06 P ART B&C MODEL QUESTION BANK FOR THE TOPIC: 9. Condensed Matter Physics UNIT-I 1 UNIT-II 17 UNIT-III 29 10. Nuclear and Particle Physics UNIT-I 77 UNIT-II 93

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*Mudra* Physical Sciences For NET & SET Exams. Of UGC-CSIR

_____________________________________________________________________________ (MCQs) Part B & C Vol-06

0

MUDRA PHYSICAL SCIENCES

VOLUME-06

PART B & C

MODEL QUESTION BANK FOR THE TOPIC:

9. Condensed Matter Physics

UNIT-I 1

UNIT-II 17

UNIT-III 29

10. Nuclear and Particle Physics

UNIT-I 77

UNIT-II 93

*Mudra* Physical Sciences For NET & SET Exams. Of UGC-CSIR

_____________________________________________________________________________ (MCQs) Part B & C Vol-06

1

9. Condensed Matter Physics UNIT-I

1. The Van der Waal crystal is –a) Argon b) Copperc) Ice d) Rock salt

2. The SI unit of atomic specific heat is –a) cal/g0C b) J/kg atom Kc) erg/g atom K d) cal/g atom 0C

3. The susceptibility of a superconductor is –a) Positive and small b) Positive and unityc) Negative and small d) Negative and unity

4. At frequencies around 14105 Hz, the ionic polarization becomes –a) Zero b) Unityc) Infinity d) Negative

5. According to band theory, the bandwidth of high energy values in comparison to those of low energy values is –

a) Small b) Largec) Equal d) Nothing can be said

6. Alignment of most molecular magnets results giving rise to magnetisation of the material even in the absence of applied field is called

a) Ferrimagnetism b) Spontaneous magnetisationc) Demagnetisation d) Paramagnetism

7. The value of magnetic flux density produced due to a current carrying coil is 1 tesla. If an iron rod is placed inside the coil, the value of magnetic flux density will –

a) Increase b) Decreasec) Remain unchanged d) Nothing can be said

8. Spin-lattice relaxation mechanisms a) Corresponds to applied fields larger than the external magnetic fieldb) Corresponds to applied fields larger than the internal magnetic fieldc) Corresponds to applied fields smaller than the internal magnetic fieldd) None of these

9. For a conventional superconductor, which of the following statements in Not true?a) Specific heat is discontinuous at transition temperature TC

b) The resistivity falls sharply at TC

c) It is diamagnetic below TC

d) It is paramagnetic below TC

*Mudra* Physical Sciences For NET & SET Exams. Of UGC-CSIR

_____________________________________________________________________________ (MCQs) Part B & C Vol-06

2

10. PET is common variety of a) Nylon 6 b) Polysterc) Nylons d) Terylene

11. A SQUID circuit consist of a) One Josephson junction b) Two Josephson junctions in parallelc) Two Josephson junctions in series d) None of these

12. The crystal lattice is a lattice in real ordinary space but the reciprocal lattice is a lattice in–a) Gaussian space b) Laplacian spacec) Fourier space d) Hypothetical space

13. For Bragg’s reflection by a crystal to occur, the X-ray wave length λ and interatomic distance d must be as –

a) d2 b) d2c) d2 d) d2

14. The maximum radius of the interstitial sphere that can just fit into the void between the body centred atom of bcc structure is

a) ]1)32[( /r b) ]1/2)3[( r

c) ]1)3[( r d) ]1)2[( r

15. The equilibrium concentration of Frenkel defect in crystals is given by –

a)

kT

ENn f

f exp~ b)

kT

ENNn f

f exp'~

c)

kT

ENNn f

f 2exp'~ d)

kT

ENNn f

f

2exp'~

16. The 2 X-ray powder diffraction pattern of ionic crystals KCl and KBr both of which form fcc structure will have

a) Pattern of KBr will have more lines b) Pattern of KCl will have more linesc) Same number of diffraction lines with equal intensities d) Number of lines will be same but their intensities will be different

17. Waves with wavelength ‘λ’ in a deep water tank are described by the dispersion relation 2/1

3

28

T , where T is surface tension and the density of water, the wave will travel?

a) Faster for longer wavelengthsb) Faster for shorter wavelengthsc) With constant speed at all wavelengthsd) With zero speed for short wavelengths

*Mudra* Physical Sciences For NET & SET Exams. Of UGC-CSIR

_____________________________________________________________________________ (MCQs) Part B & C Vol-06

3

18. Total elastic stiffness constants area) 20 b) 56c) 61 d) 21

19. The unit of Madelung constant is –a) J b) Jm/Cc) Jm/C2 d) None

20. Due to Frenkel defect, the density of the ionic solidsa) Increases b) Decreasesc) Changes d) Does not change

21. Intrinsic concentration of charge carriers in a semiconductor varies as –a) T b) T2

c) T3/2 d) 1/T

22. The probability that a state which is 0.2 eV above the Fermi energy in a metal atom at 700K is

a) 96.2% b) 62.3%c) 3.5% d) 37.7%

23. According to the free electron model, the average kinetic energy of electron at an absolute temperature T is –

a) kT2

1b) kT

2

3

c) Zero d) Infinite

24. For lead, the critical field at 0 K is 410396 . A/m and the critical temperature for zero magnetic field is 7.18 K. the value of critical field for lead at 4K is

a) 410414 . A/m b) 310413 . A/m

c) 710414 . A/m d) 410418 . A/m

25. The atomic specific heat of a solid is –a) 3R at all temperatureb) 3R at high temperatures and zero at low temperaturec) 3R at high temperatures and proportional to T3 at low temperaturesd) Proportional to T3 at all temperature

26. Find the wrong statement –a) There were regions of energy for which no bloch function solutions existb) The existence of insulators is due to the forbidden regions of energyc) Bloch functions represent perfectly free electronsd) Bloch functions are of the form exp rurki k

. where ruk

is invariant under a

crystal lattice translation

*Mudra* Physical Sciences For NET & SET Exams. Of UGC-CSIR

_____________________________________________________________________________ (MCQs) Part B & C Vol-06

4

27. HF crystal is –a) Hydrogen bonded crystal b) Vander Wall crystalc) Metallic crystal d) Ionic crystal

28. As crystal is held together entire by –a) Gravitational force b) Electrostatic forcec) Magnetic force d) Nuclear force

29. There is high degree of asymmetry in a) Network polymers b) Branched polymers c) Linear polymers d) Graft copolymers

30. The paramagnetic susceptibility of a solid varies with the absolute temperature T as a) T b) 2T

c) 0T d) 1T

31. In Debyse’s theory of specific heat of solids, the frequency of vibrations of the lattice has –a) A fixed valueb) Some discrete valuesc) A continuous spectrum upto a finite valued) A continuous spectrum upto infinity

32. The dielectric constant of water is 80. However, its refractive index is 1.75 invalidating the expression 2/1n . This is because –

a) The water molecule has a permanent dipole momentb) The boiling point of water is C1000

c) The two quantities are measured in different experimentsd) Water is transparent to visible light

33. Electrostatic attraction of charged ions of opposite sing is responsible in the bonding of ionic crystals. The electrostatic energy of a linear structure of 2N ions of charge q is nearly equal to –

a) R

qN

2

b) 2

2

R

qN

c) R

qN

22 d)

2

22

R

qN

34. If FE is the Fermi energy of a metal at 0K and fE is the Fermi energy at TK, then –

a)

22

121

F

BfF E

TkEE

b)

22

121

F

BfF E

TkEE

c)

22

121

F

BFf E

TkEE

d)

22

121

F

BFf E

TkEE

*Mudra* Physical Sciences For NET & SET Exams. Of UGC-CSIR

_____________________________________________________________________________ (MCQs) Part B & C Vol-06

5

35. The energy of a phonon is –a) b) kc) v d) Infinite

36. The packing factor of the fcc structure is –a) 52% b) 68%c) 74% d) None of these

37. Which of the following metal crystallizes in fcc structure?a) Aluminium b) Zincc) Sodium d) Caesium chloride

38. The crystal structure is NOT studied through the diffraction of –a) Electron b) Protonc) Neutron d) X-rays

39. The energy required to break up a solid into positive and negative ions is called –a) Electron affinity energy b) Coulomb repulsion energyc) Ionic cohesive energy d) Relaxation energy

40. According to Debye theory, the heat capacity of a solid at low temperature is proportional to (where α is a constant) –

a) 6T b) 3T

c) T d) T

1

41. The effective mass of an electron in a semiconductor can be –a) Negative near the bottom of the bandb) A scalar quantity with a small magnitudec) Zero at the centre of the bandd) Negative near the top of the band

42. The ratio of quantum mechanical and classical electronic specific heat is

a) TNNh

mk /B 3122

39

4 b) TN

Nh

k /B 3122

39

2

c) TNNh

mk /B 31222

39

2 d) TN

Nh

mk /B 3122

39

2

43. The total Van der Waal’s attraction energy is given by

a)

4

3

3

21 024

6

hvc

Tk

p

rE

B

b)

4

3

3

21 024

6

hvc

Tk

p

rE

B

c)

5

3

3

21 023

6

hvc

Tk

p

rE

B

d)

60

2

4

3

r

hvE

Continued on: Page 6 onwards…