Kerala SET 2018 Feb Question Paper Physics

A
18224 120 MINUTES
1. The energy of the hydrogen atom in the nth state is ------

. .
A) + B) −
C) +13.56 D) −13.56

2. If A and B are Hermitiian Operators:
A) AB + BA is Hermitian and AB – BA is not Hermitian
B) AB + BA is Hermitian and AB – BA is Hermitian
C) AB + BA is not Hermitian and AB – BA is Hermitian
D) Both AB + BA and AB – BA are not Hermitian

3. A harmonic oscillator is in the Ground state. What is the value of maximum
probability density?

A) B) C) D)
ℏ ℏ ℏ ℏ

4. The expectation value of r in the general state of hydrogen atom in terms of Bohr
radius is:
A) B) C) D)

5. For Pauli’s matrices
A) = ℏ B) =ℏ
C) =0 D) =

6. Which of the following are allowed electric dipole transitions?
A) 1 →2 B) 1 →2 C) 3 → 5 D) 2 →1

7. Light elements in stars are produced by:
A) Nuclear fission B) Nuclear fusion
C) Chemical reaction D) Nuclear transmutation

8. The de-Broglie wave length of an electron accidental through a potential difference of
V volts is:
√
A) Ǻ B) V √150 Ǻ C) Ǻ D) √150 Ǻ

9. The uncertainty relation in quantum mechanics applies to:
A) Any pair of variables
B) Pairs of dynamical variables, the operators corresponding to which commute

C) Pairs of dynamical variables, the operators corresponding to which do not
commute
D) Position and momentum only

10. A quantum mechanical system having mass m is described by the wave function
( ) = exp( )/ . The probability current density is:

ℏ ℏ ℏ ℏ
A) B) C) D)

11. A state is denoted as 4D5/2 . The value of L, S and J are:
A) L = 2, S = 3/2, J = 5/2 B) L = 5, S = 5/2, J = 3/2

C) L = 1, S = 3/2, J = 5/2 D) L = 3, S = 5/2, J = 7/2

12. The average spacing between adjacent rotational lines of CO molecule is 3.8626 cm-1.
The value of rotational constant B is -----
A) 7.7252 cm-1 B) 3.8626 cm-1
C) 1.9313 cm-1 D) 2.302 cm-1

13. For an anharmonic oscillator the selection rule Δ = ±1 corresponds to
A) Fundamental transition B) First overtone
C) Second overtone D) Third overtone

14. When an atom is placed in an external magnetic field, the electron precesses about
the field direction as axis. This precession is known as:
A) Lande’s precession B) Gyromagnetic precession
C) Pauli’s precession D) Larmor precession

15. A charge Q is placed at the centre of a cube. The electric flux through one of the face is:

A) B) C) D)

16. The electric field at a point 5 cm from a long line of charge density 2.5 x 10– 6 Cm-1 is:

A) 9 10 B) 9 10
C) 9 10 D) 9 10

17. An electron enters a magnetic field acting vertically downwards with a velocity v from
east. The electron is deflected along
A) North B) South C) North east D) South east

18. A wire of length l carries a current i along x-axis. A magnetic field exists given by
= ( + + ) T. The magnitude of magnetic force acting in the wire is:

A) B) √3 C) 2 D) √2

19. The Hall effect says that when a magnetic field B, is applied in a direction
perpendicular to the direction of current flow j , in a conductor, an electric
field produced is in the direction of :
A) B B) j C) j. B D) jxB

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20. The dimensions of ⃗ ⃗ are:
A) Power B) Energy / volume
C) Momentum / volume D) Intensity

21. Pointing Vector is:
A) ⃗ ⃗ B) ⃗ ⃗ C) ⃗ ⃗ D) ⃗ ⃗

22. Which of the following is not an electromagnetic radiation?
A) Heat rays B) X-rays C) - rays D) – rays

23. The intensity of sunlight on earth is 1300 w/m2. Assuming normal incidence, find the
magnitude of Electric field in sunlight
A) 4.9 x 105 v/m B) 7.0 x 102 v/m
5 V/m
C) 6.4 x 10 D) 8.0 x 102 v/m

24. When a ray of light enters a glass slab from air:
A) Its wavelength decreases B) Its wavelength remains unchanged
C) Its frequency increases D) Its wavelength increases

25. The sky appears blue because of:
A) Refraction B) Scattering
C) Reflection D) Total internal reflection

26. Two coherent sources of different intensities send waves that interfere. The ratio of
maximum to minimum intensity is 25. The intensity ratio of the sources is:
A) 25 : 1 B) 5:1 C) 9:4 D) 625 : 1

27. What is the fractional change in fringe width in Young’s double slit experiment if the
wavelength of incident ray is changed from 500 nm to 600 nm.
A) 20 % B) 30 % C) 40 % D) 50 %

28. In an Young’s double slit experiment, the distance between the two holes is,
0.5mm, = 5 x 10-5 cm and D = 50 cm. The fringe width will be:

A) 10-2 cm B) 5x10-2 mm C) 5x10-5 cm D) 5x10-2 cm

29. Why does a compact disc (CD) show a rainbow of colours with white light? It is due to:
A) Interference B) Diffraction
C) Scattering D) Dispersion

30. For maximum polarization of light by reflection from a plane dielectric, what is the angle
between reflected and refracted light?
A) 00 B) 450 C) 600 D) 900

31. The wavelength of Mossabauer spectrum lies in the range of:
A) X-rays B) Radio waves
C) Visible light D) Gamma rays

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32. If and are Einstein’s Coefficients of stimulated absorption and emission
respectively and g1 and g2 are the degenerates of the energy levels and
respectively, then
A) = B) =

C) = D) =1

33. The mass density of nucleus varies with its mass number as:
A) B) C) D) Remains constant

34. The energy required to break a hydrogen molecule into hydrogen atoms is:
A) 4.5 eV B) 4.5 KeV
C) 9 eV D) 10 eV

35. In the nuclear reaction 1H2 + 1 H2 → 2 H3 + 0 n1
If the mass of the deuterium atom = 2.014741 amu mass of 2 He3 atom = 3.016977 amu
and mass of neutron = 1.008987 amu, then the Q value of the reaction is nearly
A) 0.000352 Mev B) 3.27 Mev
C) 0.82 Mev D) 2.45 Mev

36. For a dielectric the polarisation vector ⃗ is given by:
A) ⃗ = ε E⃗ B) ⃗ =
⃗
C) ⃗ = ε μ E⃗ D) ⃗ = ε χE⃗

37. In the process of nuclear fission of 1 gm Uranium, the mass lost is 0.92 mg. The
efficiency of power house run by the fission reactor is 10 %. To obtain 400 megawatt
power from the power house, how much Uranium will be required per hour?
A) 174 g B) 208 g C) 416 g D) 104 g
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38. The term symbols of the ground states of Mg and 13Al are respectively:
1
A) S0 and 2P1/2 B) 1
S0 and 2P3/2
3
C) S0 and 1P1/2 D) 1
S1/2 and 2P1/2

39. The width of the energy gap of a superconductor is maximum at:
A) 0K B) Transition temperature
C) Room temperature D) None of these

40. The magnetic dipole moment is the product of current in the loop and ---
A) Flux enclosed by current loop
B) Square of area enclosed by current loop
C) Area enclosed by current loop
D) None of these

41. At Neel temperature:
A) Permeability is minimum B) Permeability is maximum
C) Susceptibility is minimum D) Susceptibility is maximum

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42. Bohr magneton is defined as:
A) Magnetic moment of an electron spin
B) Magnetic moment of a nucleus
C) Magnetic moment of an electron in orbital motion
D) Magnetic moment per unit volume of electron

43. In a simple cubic lattice d100 : d110 : d111 is :
A) 6∶ 3∶ 2 B) 6 ∶ 3 ∶ √2 C) √6 ∶ √3 ∶ √2 D) √6 ∶ √3 ∶ 2

44. The Miller indices of the plane parallel to y and z axes are:
A) (100) B) (010) C) (001) D) (111)

45. A proton and an ∝- particle has the same Kinetic energy. If the mass of the ∝- particle
is four times that of a proton, how do their de Broglie wavelength compare

∝ ∝
A) = B) = C) = 2 ∝ D) =4 ∝

46. Ohms law relates to the electric field E, conductivity and current density J as:
A) J= B) J= C) J= D) J=

47. If is the energy of the lowest state of a one dimensional potential box of length
a and is the energy of the lowest state when the length of the box is halved, then
A) = B) = C) =2 D) =4

48. If the Fermi energy of a metal is 1.4 ev, the Fermi temperature of the metal is
approximately:
A) 1.6 x 104 K B) 1.6 x 103 K C) 1.6 x 102 K D) 1.6 x 105 K

49. The spacing between the nth energy level and the next higher level in an one dimensional
potential box increases by:
A) (2n – 1) B) (2n + 1) C) (n – 1) D) (n+1)

50. Four physical quantities are given in Column I and their order of values in Column II.
Match approximately
Column I Column II
a. Thermal energy of air at room temperature 1. 0.02 ev
b. Binary energy of heavy nuclei per nucleon 2. 2 ev
c. X-ray Photon energy 3. 10 kev
d. Photon energy of visible light 4. 7 Mev

A) a-1, b-4, c-3, d- 2 B) a-2, b-1, c-3, d-4
C) a-3, b-4, c-2, d-1 D) a-4, b-3, c-2, d-1

51. AND gate can be produced using two ----- gates.
A) NOT B) NOR C) XOR D) NAND

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52. The space lattice of sodium chloride crystal is:
A) fcc B) bcc
C) simple cubic D) orthorhombic

53. Which of the following device is a negative resistance device?
A) Triode B) Transistor
C) Thyristor D) Zener diode

54. When base current is changed from 30 to 80 , the collector current changes from
1 to 3.5 . The current gain in C-E configuration is:
A) 50 B) 75 C) 100 D) 125

55. Two amplifiers of gain and are RC coupled, then the net gain is:
A) + B) − C) D)

56. The number of flip-flops needed to construct a shift register capable of storing a 6- bit
Binary number is:
A) 6 B) 4 C) 2 D) 12

57. The output voltage of a 6-bit binary ladder with the input 101001 is:
A) 0.641 v B) 0.923 v C) 0.766 v D) 0.810 v

58. The relation between ∝ and parameters of a transistor are given by:
A) ∝= B) ∝= C) ∝= D) ∝=

59. Which of the following has the highest input resistance?
A) NPN transistor in C B configuration
B) PNP transistor in C E configuration
C) N type channel JFEP
D) P type channel MOSFET

60. For a Germanium P-N junction, the maximum value of barrier potential is:
A) 0. 3 v B) 0. 7 v C) 1. 3 v D) 1. 7 v

61. If the lattice temperature is increased, the Hall coefficient of a semiconductor will
A) Decrease
B) Increase
C) First increases and then deceases
D) Remain constant

62. A Solar cell is actually a device which utilises:
A) Photo conductive effect B) Photo voltaic effect
C) Photo emissive effect D) Photo resistive effect

63. A Schmitt trigger converts slowly varying wave form into:
A) Sine wave B) Saw tooth wave
C) Triangular wave D) Square wave

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64. For two vectors ⃗ and ⃗, │ ⃗ + ⃗│ = │ ⃗ − ⃗│only when

A) │ ⃗ │= │ ⃗│≠ 0

B) ⃗⊥ ⃗

C) │ ⃗ │= │ ⃗│≠ 0 and ⃗ and ⃗ are parallel

D) │ ⃗ │= │ ⃗│≠ 0 and ⃗ and ⃗ are antiparallel

65. Three vectors add to zero, as in the right triangle. The value of ⃗ . ⃗ is:

A) 0 B) ab C) 1 D) infinity

66. The value of the gamma function: Γ( ) is:
A) 1 B) C) √ D) 0

67. If │ ⃗ │= 2 and │ ⃗│= 4, then match the relations in Column I with the angle
between ⃗ and ⃗ in Column II
Column I Column II
a. ⃗. ⃗=0 1. =0
b. ⃗ . ⃗ = +8 2. = 900
c. ⃗. ⃗=4 3. = 1800
d. ⃗ . ⃗ = −8 4. = 600

A) a-2, b-1, c-4, d-3 B) a-1, b-2, c-4, d-3
C) a-3, b-4, c-1, d-2 D) a-4, b-1, c-2, d-3

68. The relationship between the Bessel functions J n ( x) and J  n ( x) is:

A) ( )= − ( ) B) ( )= ( )

C) ( ) = (−1) ( ) D) ( ) = (−1) ( )

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69. Which of the following is not a unit of time?
A) Second B) Par second
C) Year D) Micro second

70. The value of the integral ∫ is:
A) 1 B) C) D)

71. The component of a vector ⃗ along X-axis will have maximum value if:
A) ⃗ is along positive Y-axis
B) ⃗ is along positive X-axis
C) ⃗ makes an angle of 450 with the X-axis
D) ⃗ is along negative Y-axis

72. An object of mass m moves to the right with a speed . It collides head on in a
perfectly inelastic collision with an object twice the mass but half the speed moving in
the opposite direction. What is the speed of the combined mass after collision?
A) 0 B) C) D) 2

73. A system of N particles is forced with k constraints, then the degree of
freedom of the system is:
A) 3N B) 3N-k C) N-k D) k -N

74. If the Lagrangian of a system is = ( ̇ + ̇ + ̇ ) , then:
A) r alone is a cyclic coordinate
B) z alone is a cyclic coordinate
C) z and r are cyclic coordinates
D) and r are cyclic coordinates

75. The angular momentum L of a rotating object is:
A) B) C) ∝ D) ∑

76. The equation of a progressive wave is

=8 − +
The wavelength of the wave is:
A) 8m B) 4m C) 2m D) 10 m

77. A particle is executing motion = cos( − θ). The maximum velocity of the
particle is:
A) B) θ C) θ D) θ

78. =4 +3 is the equation of a particle executing SHM. The initial phase
angle is:
A) ( ) B) ( ) C) ( ) D) ( )

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79. According to Stefan’s law, the internal energy of a thermal system at temperature T is
proportional to:

A) T3 B) T4 C) its volume D) its pressure

80. In superconductors electrons form Cooper pairs. This pairing is due to:
A) Electrostatic forces
B) Magnetic interactions
C) Interaction of electrons with the lattice
D) Interaction of electrons with photons

81. The energy differences between the spin up and spin down states of a proton in a
magnetic field of B = 1.0 T is:
A) 24. 0 10 B) 12. 2 10
C) 8. 7 10 D) 1. 76 10

82. A stationary body explodes into two fragments each of mass 1.0 Kg that move apart at
speeds or 0.6c relative to the original body. The mass of the original body is:
A) 2.5 kg B) 5.0 kg C) 1.0 kg D) 1.5 kg

83. Spacecraft Alpha is moving at 0.90c with respect to the earth. If spacecraft Beta is to pass
Alpha at a relative speed of 0.5c in the same direction, what speed must Beta have with
respect to the earth?
A) 0.30 c B) 0.52 c C) 0.97 c D) 0.12 c

84. At what speed does the Kinetic energy of a particle equal to its rest energy?

√ √ √ √
A) B) C) D)

85. If 1 kg of a substance is fully converted into energy, how much energy is produced?
A) 3 10 J B) 9 10 J C) 1.5 10 J D) 4.5 10 J

86. The momentum (in ∕ ) of a electron whose speed is 0.60c is

A) 0. 38 ∕ B) 0. 42 ∕ C) 0.51 ∕ D) 0.72 ∕

87. A proton is confined to a nucleus of radius 5 10 . The minimum uncertainty in
momentum is:
A) 1.05 10 B) 1.05 10

C) 2. 80 10 D) 2.01 10

88. If v is the velocity of a distant galaxy at a distance of r from us, then
Hubble’s law states that ( H is the Hubble’s constant):
A) v = H r2 B) v = H r-1 C) v = Hr D) v = H r-2

89. The quark content of proton is:
A) ud B) dud C) dd D) uud

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90. Choose the wrong answer
A) Nuclear force is non-central
B) Nuclear force is charge independent
C) Nuclear force does not obey inverse square law
D) Nuclear force is charge dependent

91. The value of spin for the particle P ion is:
A) 0 B) + C) + D) +1

92. The charges of up Quark and down Quark are:
A) + − B) + −

C) + − D) + −

93. A particle linked to the x-axis has the wave function = between = 0 =1
= 0 elsewhere. The expectation value < > of the particle position is:

A) B) C) D)

94. An eigen function of the operator is = . The corresponding eigen value is:
A) 1 B) 2 C) 4 D) 6

95. Electron with energy of 1 ev is incident on a barrier 10.0 ev high and 0.50 nm wide. The
transmission probability is nearly
A) 10 B) 10 C) 10 D) 10

96. A student writes the wave function of a free particle as
( ) = exp [ ( − )]
This is not correct because:
A) It is not normalizable
B) It does not satisfy the wave equation
C) The sign of the first term in the exponent is wrong
D) It does not satisfy the required boundary conditions

97. The Pauli’s Exclusion principle is:
A) A consequence of identity of particles
B) Follows from Bohr’s quantization rules
C) Follows from the Schrodinger wave equation
D) Necessary to explain the periodic table

98. If = , what values of l are possible
A) 2, 3 B) 1, 4 C) 5, 7 D) ,

99. Atoms are neutral. When they combine to form molecules, the force between them
which is responsible for binding is:
A) Nuclear force B) Gravitational force
C) Electromagnetic force D) Vanderwaal force

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100. When a conductor becomes a superconductor its specific heat capacity
A) Remains unaltered
B) Decreases continuously
C) Increases showing a discontinuity at the transition temperature
D) Decreases showing a discontinuity at the transition temperature

101. Hyperfine splitting of atomic spectral lines is due to,
A) Spin-orbit coupling
B) The effect of nuclear spin on the electron angular momentum
C) Application of external magnetic field
D) Application of external electric field

102. The rate at which information can be carried through a communication channel
depends on
A) Transmission loss B) Transmitted power
C) Bandwidth D) None of the above

103. The role of a moderator in a reactor is:
A) To slow down neutrons
B) To prevent harmful radiation to escape
C) To produce neutrons
D) To monitor the nuclear reaction

104. In a particle detector, positively and negatively charged particles can very often be
distinguished. This is because:
A) Their ionization properties are different
B) They curve differently in a magnetic field
C) The reactions which produce them have different characteristics
D) Only negatively charged one react strongly with atomic nuclei

105. A plane electromagnetic wave of frequency 25 MHz travels in free space along x-
direction. At a particular point in space and time, ⃗ = 6. 3 . The value of ⃗
at this point is:
A) 2. 1 10 T B) 2. 1 10 ̂T
C) 0. 4 10 T D) 0. 48 10 ̂ T

106. The frequencies of X-rays, - rays and Ultraviolet rays are respectively a, b and c.
Then:
A) a < b, b > c B) a > b, b > c C) a > b, b < c D) a < b, b < c

107. If represent the permittivity and permeability of vacuum and and
represent the permittivity and permeability of medium, then refractive index of the
medium is given by:

A) B) C) D)

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108. A thin spherical shell of radius a has total charge Q distributed uniformly over its surface.
The electric field inside the shell is:
A) . B) . C) 0 D) Infinite

109. The electric field due to a non conducting infinite charge per unit area is:
A) B) C) D) 0

110. A thin Copper rod 1.0 m long has a mass of 50 g. What is the minimum current in the rod
and would allow it to “float” in a magnetic field of 0.1 T
A) 1.2 A B) 2. 5 A C) 4. 9 A D) 9. 8 A

111. A bar magnet is falling through a loop of wire with constant velocity with the North Pole
entering first. Viewed from the same side of coil as the magnet, as the North Pole enters
the wire, the direction of the induced current will be:
A) Clockwise B) Counter clockwise
C) Zero D) Along the length of magnet

112. What is the time constant for the circuit shown?

A) B) C) D)

113. The frequency of oscillation of an L C circuit is:
√ √
A) B) C) D)
√ √

114. Which one of the following is not a Boolean identity?
A) + = B) + = +
C) + = D) ( + )=

115. Which of the following molecules would show a microwave (rotational) spectrum?
A) Br2 B) H Br C) CS2 D) None of the above

116. The longest wavelength present in the Balmer series of hydrogen, corresponding to
H∝ line is:
A) 656 nm B) 1312 nm C) 6560 nm D) 13120 nm

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117. A helium – neon laser is:
A) Solid state laser B) Two–level laser
C) Three–level laser D) Four–level laser

118.
A B Y
0 0 1
1 0 1
0 1 1
1 1 0

The above truth table corresponds to:

A) OR gate B) NOR gate C) AND gate D) NAND gate

119. Resistance of a semiconductor:
A) Decreases with increase in temperature
B) Increases with increase in temperature
C) Increases for Germanium and decreases for Silver
D) Is not affected by charge in temperature

120. For a common base amplifier the power gain is:
A) B) C) + D)

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