PHYSICS- PAGE 3
1. In a series LCR circuit the resonant frequency is 1000 Hz . The half power points are obtained at frequencies 950 Hz and 1050 Hz. What are the quality factor and bandwidth of the circuit respectively ?
1) 100, 100 Hz
2) 10, 100 Hz
3) 10, 10 Hz
4) 100, 10 Hz
Ans: 2
2. The two basic component of a Thevenin equivalent ac circuit are ;
1) The equivalent voltage source and the equivalent parallel resistance
2) The equivalent voltage source and the equivalent parallel impedence
3) The equivalent voltage source and the equivalent series resistance
4) The equivalent voltage source and the equivalent series impedence
Ans: 3
3. In applying the Superposition theorem:
1) All Sources are considered independently
2) The Sources are considered one at a time with all others replaced by their internal impedence
3) All Sources are considered simultaneously
4) The Sources are considered one at a time with all others replaced by their internal resistance
Ans: 2
4. Nortan theorem gives :
1) an equivalent voltage source in parallel with an equivalent impedence
2) an equivalent current source in series with an equivalent impedence .
3) an equivalent current source in parallel with an equivalent impedence
4) an equivalent voltage source in series with an equivalent impedence
Ans: 3
5. The built in potential of a p-n junction diode is a function of :
1) temperature
2) biased voltage
3) doping density
4) All of these
Ans: 4
6. In an n-type Semiconductor the Fermi level lies 0.3 eV below the conduction band at 300 K. If the temperature is increased to 330 K, where does the new position of the Fermi level lie ?
1) 0.55 eV below the conduction band
2) 0.44 eV below the conduction band
3) 0.33 eV below the conduction band
4) 0.27 eV below the conduction band
Ans: 4
7. Flow of electrons is affected by the following:
1) thermal vibrations
2) Impurity atoms
3) Crystal defects
4) All of these
Ans: 4
8. An n-type Semiconductor is :
1) Positively charged
2) Negatively charged
3) Electrically neutral
4) None of these
Ans: 3
9. A hole in a Semiconductor is defined as :
1) a free electron
2) The incomplete part of an electron pair bond
3) A free proton
4) A free neutron
Ans: 2
10. As the doping to a pure semiconductor increases, the bulk resistance of the semiconductor :
1) Remains the same
2) Increases
3) Decreases
4) None of these
Ans: 3
11. With forward bias to an p-n function , the width of depletion layer :
1) Decreases
2) Increases
3) Remains the same
4) None of these
Ans: 1
1) 100, 100 Hz
2) 10, 100 Hz
3) 10, 10 Hz
4) 100, 10 Hz
Ans: 2
2. The two basic component of a Thevenin equivalent ac circuit are ;
1) The equivalent voltage source and the equivalent parallel resistance
2) The equivalent voltage source and the equivalent parallel impedence
3) The equivalent voltage source and the equivalent series resistance
4) The equivalent voltage source and the equivalent series impedence
Ans: 3
3. In applying the Superposition theorem:
1) All Sources are considered independently
2) The Sources are considered one at a time with all others replaced by their internal impedence
3) All Sources are considered simultaneously
4) The Sources are considered one at a time with all others replaced by their internal resistance
Ans: 2
4. Nortan theorem gives :
1) an equivalent voltage source in parallel with an equivalent impedence
2) an equivalent current source in series with an equivalent impedence .
3) an equivalent current source in parallel with an equivalent impedence
4) an equivalent voltage source in series with an equivalent impedence
Ans: 3
5. The built in potential of a p-n junction diode is a function of :
1) temperature
2) biased voltage
3) doping density
4) All of these
Ans: 4
6. In an n-type Semiconductor the Fermi level lies 0.3 eV below the conduction band at 300 K. If the temperature is increased to 330 K, where does the new position of the Fermi level lie ?
1) 0.55 eV below the conduction band
2) 0.44 eV below the conduction band
3) 0.33 eV below the conduction band
4) 0.27 eV below the conduction band
Ans: 4
7. Flow of electrons is affected by the following:
1) thermal vibrations
2) Impurity atoms
3) Crystal defects
4) All of these
Ans: 4
8. An n-type Semiconductor is :
1) Positively charged
2) Negatively charged
3) Electrically neutral
4) None of these
Ans: 3
9. A hole in a Semiconductor is defined as :
1) a free electron
2) The incomplete part of an electron pair bond
3) A free proton
4) A free neutron
Ans: 2
10. As the doping to a pure semiconductor increases, the bulk resistance of the semiconductor :
1) Remains the same
2) Increases
3) Decreases
4) None of these
Ans: 3
11. With forward bias to an p-n function , the width of depletion layer :
1) Decreases
2) Increases
3) Remains the same
4) None of these
Ans: 1
12. A single transistor can be used to build which of the following digital logic gate :
1) AND Gate
2) NOT Gate
3) OR Gate
4) NAND Gate
Ans: 2
13. A NAND Gate has:
1) LOW inputs and a High output
2) HIGH inputs and a HIGH output
3) LOW inputs and a LOW output
4) None of these
Ans: 1
14. What input values will cause an AND logic gate to produce a HIGH output ?
1) Atleast one input is LOW
2) Atleast one input is HIGH
3) All inputs are HIGH
4) All inputs are LOW
Ans: 3
15. The maximum number of electrons that can be accomodated by p- orbital is :
1) 2
2) 6
3) 10
4) 4
Ans: 2
16. Quantum number value for 2p Subshells are :
1) n = 1, L = 1
2) n = 2, L = 1
3) n = 1, L = 0
4) n = 2, L = 0
Ans: 2
17. Principal quantum number describes:
1) Shape of orbital
2) Spin of orbital
3) Size of orbital
4) Orientation of an orbital
Ans: 3
18. No two electrons in the same atom can have identical set of four quantum numbers , The statement is known as:
1) (n+1) rule
2) Aufbaus rule
3) Hund's rule
4) Pauli's exclusion principle
Ans: 4
19. Which of the following statement is wrong about electron :
1) Its motion is affected by magnetic field
2) It has wave like property
3) It is a particle
4) It emits energy while moving in atomic orbit
Ans: 4
20. For a three dimensional crystal having N primitive unit cells with a basis of p-atoms , the number of optical branches is :
1) 3
2) 3p
3) 3p 3
4) 3N 3p
Ans: 3
21. An atom with one outer electron having orbital angular momentum l is placed in a weak magnetic field. The number of energy levels into which the higher total angular momentum state splits , is:
1) 2l +2
2) 2l + 1
3) 2l
4) 2l 1
Ans: 1
22. Protons resonates in a high field nuclear magnetic resonance spectrometer at frequencies close to 800 MHz. Calculate the strength of the magnetic field of the spectrometer.
1) 10.0 T
2) 12.0 T
3) 18.8 T
4) 21.2 T
Ans: 3
23. What will happen if the primary of a transformer is connected to DC supply ?
1) Transformer will operate with low efficiency
2) Transformer will operate with high efficiency
3) No effect
4) Transformer may start to smoke and burn
Ans: 4
24. What will happen if a power transformer designed for operation on 50 Hz frequency were connected to 500 Hz frequency source of the same voltage ?
1) Current will be too much high
2) Transformer may start to smoke and burn
3) Eddy current and Hysteresis loss will be excessive
4) No effect
Ans: 3
25. In a Ruby Laser the atoms are excited by :
1) Ruby rod
2) Flash tube
3) Silvered mirror
4) Semi transparent mirror
Ans: 2
1) AND Gate
2) NOT Gate
3) OR Gate
4) NAND Gate
Ans: 2
13. A NAND Gate has:
1) LOW inputs and a High output
2) HIGH inputs and a HIGH output
3) LOW inputs and a LOW output
4) None of these
Ans: 1
14. What input values will cause an AND logic gate to produce a HIGH output ?
1) Atleast one input is LOW
2) Atleast one input is HIGH
3) All inputs are HIGH
4) All inputs are LOW
Ans: 3
15. The maximum number of electrons that can be accomodated by p- orbital is :
1) 2
2) 6
3) 10
4) 4
Ans: 2
16. Quantum number value for 2p Subshells are :
1) n = 1, L = 1
2) n = 2, L = 1
3) n = 1, L = 0
4) n = 2, L = 0
Ans: 2
17. Principal quantum number describes:
1) Shape of orbital
2) Spin of orbital
3) Size of orbital
4) Orientation of an orbital
Ans: 3
18. No two electrons in the same atom can have identical set of four quantum numbers , The statement is known as:
1) (n+1) rule
2) Aufbaus rule
3) Hund's rule
4) Pauli's exclusion principle
Ans: 4
19. Which of the following statement is wrong about electron :
1) Its motion is affected by magnetic field
2) It has wave like property
3) It is a particle
4) It emits energy while moving in atomic orbit
Ans: 4
20. For a three dimensional crystal having N primitive unit cells with a basis of p-atoms , the number of optical branches is :
1) 3
2) 3p
3) 3p 3
4) 3N 3p
Ans: 3
21. An atom with one outer electron having orbital angular momentum l is placed in a weak magnetic field. The number of energy levels into which the higher total angular momentum state splits , is:
1) 2l +2
2) 2l + 1
3) 2l
4) 2l 1
Ans: 1
22. Protons resonates in a high field nuclear magnetic resonance spectrometer at frequencies close to 800 MHz. Calculate the strength of the magnetic field of the spectrometer.
1) 10.0 T
2) 12.0 T
3) 18.8 T
4) 21.2 T
Ans: 3
23. What will happen if the primary of a transformer is connected to DC supply ?
1) Transformer will operate with low efficiency
2) Transformer will operate with high efficiency
3) No effect
4) Transformer may start to smoke and burn
Ans: 4
24. What will happen if a power transformer designed for operation on 50 Hz frequency were connected to 500 Hz frequency source of the same voltage ?
1) Current will be too much high
2) Transformer may start to smoke and burn
3) Eddy current and Hysteresis loss will be excessive
4) No effect
Ans: 3
25. In a Ruby Laser the atoms are excited by :
1) Ruby rod
2) Flash tube
3) Silvered mirror
4) Semi transparent mirror
Ans: 2
26. Which is more elastic?
A:-Glass
B:-Concrete
C:-Steel
D:-Rubber
Ans: C
27. A liquid drop is spherical in shape due to
A:-Viscosity
B:-Capillarity
C:-Buoyancy
D:-Surface Tension
Ans: D
28. When a stone is thrown vertically above,the acceleration at the top is
A:-g
B:-0
C:--g
D:-0.5g
Ans: A
29. When temperature increases,the electrical conductivity of a semiconductor
A:-Increases
B:-Decreases
C:-First increases and then decreases
D:-No change
Ans: A
A:-Glass
B:-Concrete
C:-Steel
D:-Rubber
Ans: C
27. A liquid drop is spherical in shape due to
A:-Viscosity
B:-Capillarity
C:-Buoyancy
D:-Surface Tension
Ans: D
28. When a stone is thrown vertically above,the acceleration at the top is
A:-g
B:-0
C:--g
D:-0.5g
Ans: A
29. When temperature increases,the electrical conductivity of a semiconductor
A:-Increases
B:-Decreases
C:-First increases and then decreases
D:-No change
Ans: A
30:-A network contains linear resistor and ideal voltage sources. If value of all the resistors are doubled, then voltage across each resistor is
A:-Halved
B:-Doubled
C:-Not changed
D:-Increase 4 times
Ans: C
31:-The current i(t) through a 10 ohm resistance in series with an inductance is given by i(t) = 3 + 4 sin (100t +45°) + 4 sin (300t + 60°)A. The rms value of current and power dissipated in the circuit are
A:-`sqrt(41)` A, 410 W respectively
B:-`sqrt(35)`A, 380 W respectively
C:-5 A, 250 W respectively
D:-11 A, 1210 W respectively
Ans: C
32:-In full wave rectification, if the input frequency is 50 Hz, then the output frequency will be
A:-50 Hz
B:-75 Hz
C:-100 Hz
D:-200 Hz
Ans: C
33:-A fully charged 12 V, 100 Ah battery is connected to a 1.2 Ω load. The expected time for which the battery can supply power to load is
A:-10 hours
B:-12 hours
C:-1.2 hours
D:-144 hours
Ans: A
34:-A microcontroller normally has which of the following devices on chip?
A:-RAM
B:-ROM
C:-I/O ports
D:-All of the above
Ans: D
35:-GaAs LED's emit radiation in the
A:-Ultraviolet region
B:-Blue-green region of visible region
C:-Orange-red range of visible region
D:-Infra red region
Ans: D
36:-The function of Network and Switching Subsystem (NSS) in GSM is to
A:-Provide and manage radio transmission path between the mobile stations and the Mobile Switching Centre (MSC)
B:-Manage the switching functions of the system and allows the Mobile Switching Centre (MSC) to communicate with other networks
C:-Supports the operation and maintenance of GSM
D:-Manage the radio interface between the mobile station and all other subsystems of GSM
Ans: B
A:-Halved
B:-Doubled
C:-Not changed
D:-Increase 4 times
Ans: C
31:-The current i(t) through a 10 ohm resistance in series with an inductance is given by i(t) = 3 + 4 sin (100t +45°) + 4 sin (300t + 60°)A. The rms value of current and power dissipated in the circuit are
A:-`sqrt(41)` A, 410 W respectively
B:-`sqrt(35)`A, 380 W respectively
C:-5 A, 250 W respectively
D:-11 A, 1210 W respectively
Ans: C
32:-In full wave rectification, if the input frequency is 50 Hz, then the output frequency will be
A:-50 Hz
B:-75 Hz
C:-100 Hz
D:-200 Hz
Ans: C
33:-A fully charged 12 V, 100 Ah battery is connected to a 1.2 Ω load. The expected time for which the battery can supply power to load is
A:-10 hours
B:-12 hours
C:-1.2 hours
D:-144 hours
Ans: A
34:-A microcontroller normally has which of the following devices on chip?
A:-RAM
B:-ROM
C:-I/O ports
D:-All of the above
Ans: D
35:-GaAs LED's emit radiation in the
A:-Ultraviolet region
B:-Blue-green region of visible region
C:-Orange-red range of visible region
D:-Infra red region
Ans: D
36:-The function of Network and Switching Subsystem (NSS) in GSM is to
A:-Provide and manage radio transmission path between the mobile stations and the Mobile Switching Centre (MSC)
B:-Manage the switching functions of the system and allows the Mobile Switching Centre (MSC) to communicate with other networks
C:-Supports the operation and maintenance of GSM
D:-Manage the radio interface between the mobile station and all other subsystems of GSM
Ans: B
37:-The primary function of a surge tank is to
A:-Store excess water from tail race
B:-Increase power output from the turbine
C:-Act as container for surge arrester
D:-Prevent pressure wave due to water hammer in penstock
Ans: D
38:-A universal joint allow the propeller shaft to
A:-bend sideways
B:-change length
C:-transfer torque at an angle
D:-change inclination
Ans: C
39:-The function of an economizer in a steam power plant is to
A:-increase the temperature of supply air
B:-increase the temperature of feed water
C:-condense the exhaust steam from the turbine
D:-preheat the fuel
Ans: B
40:-The compression ignition engines are governed by
A:-Hit and miss governing
B:-Quantity governing
C:-Quality governing
D:-Combination of (2) and (3)
Ans: C
41:-The speed ratio between crankshaft and camshaft is
A:-2 : 1
B:-4 : 1
C:-1 : 2
D:-1 : 4
Ans: A
A:-Store excess water from tail race
B:-Increase power output from the turbine
C:-Act as container for surge arrester
D:-Prevent pressure wave due to water hammer in penstock
Ans: D
38:-A universal joint allow the propeller shaft to
A:-bend sideways
B:-change length
C:-transfer torque at an angle
D:-change inclination
Ans: C
39:-The function of an economizer in a steam power plant is to
A:-increase the temperature of supply air
B:-increase the temperature of feed water
C:-condense the exhaust steam from the turbine
D:-preheat the fuel
Ans: B
40:-The compression ignition engines are governed by
A:-Hit and miss governing
B:-Quantity governing
C:-Quality governing
D:-Combination of (2) and (3)
Ans: C
41:-The speed ratio between crankshaft and camshaft is
A:-2 : 1
B:-4 : 1
C:-1 : 2
D:-1 : 4
Ans: A
42:-Which among the following is not true about amplitude modulation ?
A:-Carrier wave is a pulse
B:-Carrier wave is sinusoidal
C:-Carrier wave is of high frequency
D:-The frequency of the carrier wave is modulated
Ans: D
43:-Name the plant hormone responsible for active cell division
A:-Absisic acid
B:-Auxin
C:-Cytokinin
D:-Gibberellin
Ans: C
44:-Which of the following sets of quantum numbers is not possible ?
A:-n = 1, l = 0, m = 0, s = + 1/2
B:-n = 2, l = 2, m =- 2, s = -1/2
C:-n = 3, l = 2, m = -2, s = +1/2
D:-n = 2, l = 1, m = -1, s = + 1/2
Ans: B
45:-Who proposed mutation theory ?
A:-Charles Darwin
B:-T. H. Morgan
C:-Hugo de Vries
D:-Gregor Mendel
Ans: C
46:-The image formed by the objective of a compound microscope is
A:-Real and enlarged
B:-Virtual and enlarged
C:-Real and diminished
D:-Virtual and diminished
Ans: A
47:-As we go from the equator to the poles, our weight
A:-Decreases
B:-Increases
C:-Decreases upto a latitude of 45°
D:-Remains the same
Ans: B
48:-Which of the following thermodynamic quantities is not a state function ?
A:-Work
B:-Gibb's free energy
C:-Internal energy
D:-Enthalpy
Ans: A
A:-Carrier wave is a pulse
B:-Carrier wave is sinusoidal
C:-Carrier wave is of high frequency
D:-The frequency of the carrier wave is modulated
Ans: D
43:-Name the plant hormone responsible for active cell division
A:-Absisic acid
B:-Auxin
C:-Cytokinin
D:-Gibberellin
Ans: C
44:-Which of the following sets of quantum numbers is not possible ?
A:-n = 1, l = 0, m = 0, s = + 1/2
B:-n = 2, l = 2, m =- 2, s = -1/2
C:-n = 3, l = 2, m = -2, s = +1/2
D:-n = 2, l = 1, m = -1, s = + 1/2
Ans: B
45:-Who proposed mutation theory ?
A:-Charles Darwin
B:-T. H. Morgan
C:-Hugo de Vries
D:-Gregor Mendel
Ans: C
46:-The image formed by the objective of a compound microscope is
A:-Real and enlarged
B:-Virtual and enlarged
C:-Real and diminished
D:-Virtual and diminished
Ans: A
47:-As we go from the equator to the poles, our weight
A:-Decreases
B:-Increases
C:-Decreases upto a latitude of 45°
D:-Remains the same
Ans: B
48:-Which of the following thermodynamic quantities is not a state function ?
A:-Work
B:-Gibb's free energy
C:-Internal energy
D:-Enthalpy
Ans: A
49. In a simple scattering problems, the mathematical expression for scattered flux is dN = σ(θ, φ)N nd Ω. The term σ(θ, φ) expresses the :
(a) total scattering cross-section (b) differential scattering cross-section
(c) scattered angular flux (d) number of fixed scattering centres
Ans: B
50. Particles of energy 9 eV are sent towards a potential step of height 8 eV. The percentage of particles reflected back is
(a) 25% (b) 50%
(c) 75% (d) No particle will be reflected
Ans: A
51. The Yukawa potential is static and spherically symmetric solution to the
(a) Schrödinger equation (b) Dirac equation
(c) Klein-Gordon equation (d) None of the above
Ans: C
52. The magnitude of the linear momentum of a photon in a beam of He-Ne laser having wavelength λ = 634 nm will be in eV/c as :
(a) 1.96 (b) 2.20 (c) 1.80 (d) 1.90
Ans: A
53. The group velocity of matter is
(a)1 less than particle velocity (b) greater than particle velocity
(c) equal to particle velocity (d) same as phase velocity
Ans: C
54. If an oscillator is in its ground state, then the probability of finding the particle outside the classical limits is approximately
(a) 16% (b) 24% (c) 48% (d) 84%
Ans: A
55. Which of the following is its own anti-particle ?
(a) π° (Neutral pion) (b) k° (Neutral kaon)
(c) ∧° (Neutral Lambda Hyperon) (d) N (Neutron)
Ans: A
56. Deviation of a nuclear charge distribution from spherical symmetry defines :
(a) Its spin angular momentum (b) Its electric dipole moment
(c) Its electric quadrupole moment (d) The monopole moment
Ans: C
57. The Baryon number is 1 for
(a) Proton (b) µ-meson
(c) π-meson (d) Lepton
Ans: A
58. Σ-baryons exist in three charged states -1, 0 and + 1. It has strangeness (s) :
(a) – 2 (b) – 1 (c) 1 (d) 0
Ans: B
59. A gamma-ray photon creates an electron – positron pair. If the rest mass of electron is 0.5 MeV and total kinetic energy of the pair is 0.78 MeV, the energy of gamma-ray must be
(a) 0.28 MeV (b) 1.28 MeV (c) 1.78 MeV (d) 0.78 MeV
Ans: C
60. Which one of the following statements is true that nuclear forces are
(a) Long range forces (b) Central forces
(c) Exchange forces (d) Unsaturated forces
Ans: C
61. In a Vande Graff accelerator, ion source injects proton in the accelerating tube in the high voltage dome. 7 MV potential is applied to the dome. The kinetic energy of the proton after acceleration will be
(a) 14 MeV (b) 9.5 MeV (c) 8.4 MeV (d) 7 MeV
Ans: D
62. A nucleus will disintegrate into parts if the mass defect relative to these parts is
(a) Positive (b) Negative
(c) Zero (d) Both Positive and Negative
Ans: A
63. Atomic nuclei with same number of neutrons or protons equal to magic numbers, are exceptionally
(a) low Z-nuclei (b) radioactive in nature
(c) stable (d) weak
Ans: C
64. When electromagnetic wave passes from one medium to another, the boundary condition is
(a) normal component of electric field vector is continuous.
(b) normal component of magnetic field vector is continuous.
(c) parallel component of electric field vector is not continuous.
(d) parallel component of magnetic field vector is continuous.
Ans: B
65. A point charge q is placed at a distance d from an earthed conducting sphere (initially uncharged) of radius R(R < d). Now earthing is removed and then charge q is moved to infinite. Charge on the sphere now will be
(a) zero (b) q/2
(c) – qR/d (d) None of the above
Ans: C
66. Fine structure of Hydrogen α-line is explained by
(a) Bohr atom model
(b) Rutherford atom model
(c) Spin orbit interaction combined with relativistic correction
(d) Sommerfeld elliptical method with relativistic correction and spin of electron.
Ans: D
67. The quantum of Lattice vibration is known as a
(a) photon (b) phonon (c) Graviton (d) Gluon
Ans: B
68. When a magnetic material is subjected to an external magnetizing field, its ability to get
magnetized is described in terms of
(a) Magnetic permeability (b) Magnetic susceptibility
(c) Magnetic viscosity (d) Magnetic resonance
Ans: B
69. The quartz crystal is an example of
(a) A negative uniaxial crystal (b) A positive uniaxial crystal
(c) A biaxial crystal (d) None of the above
Ans: B
70. The super conductors are
(a) Perfect ferromagnetics (b) Perfect paramagnetics
(c) Perfect diamagnetics (d) perfect anti-ferromagnetics
Ans: C
71. A crystal system whose unit cell is specified by a = b ≠ c, α = β = γ = 90° (where a, b, c
and α, β, γ have their usual meaning) is known as
(a) Monoclinic (b) Orthorhombic
(c) Tetragonal (d) Rhombohedral
Ans: C
72. In any radio receiver, the active device used for demodulation is
(a Triode (b) Tetrode (c) Pentode (d) Diode
Ans: D
73. The hexadecimal number 3C is equivalent to decimal number
(a) 60 (b) 40 (c) 20 (d) 85
Ans: A
74. Which one of the following is not a basic logic gate ?
(a) OR (b) AND (c) XOR (d) NOT
Ans: C
75. Bubbled (inverted) inputs OR gate is equivalent to a
(a) NOR gate (b) NAND gate (c) XNOR gate (d) XOR gate
Ans: B
76. Mobility of charge carrier is
(a) Velocity per unit applied voltage (b) Velocity per unit applied electric field
(c) Velocity per unit current (d) Variation of velocity with temperature
Ans: B
77. Indicate the false statement from the following statements for a Zener diode whose breakdown voltage is 4.7 volts :
(a) Zener diode is constructed from heavily doped material.
(b) Breakdown occurs due to collision of high velocity minority carrier.
(c) Breakdown is due to high electric field across the depletion region.
(d) Tunnelling of minority carrier through the junction.
Ans: B
78. Which type of negative feedback is used in a buffer amplifier ?
(a) Voltage series (b) Current series
(c) Voltage shunt (d) Current shunt
Ans: A
79. If we apply AC voltage V = Vp sin ωt at the input of a half wave rectifier then the output DC voltage without using any filter in circuit is
(a) Vp/π (b) 2 Vp/π (c) Vp/2π (d) Vp/2
Ans: A
80. When a rigid body rotates about a given axis, the degrees of freedom associated with it will be
(a) 1 (b) 3 (c) 2 (d) 4
Ans: A
81. For a non-relativistic free particles the phase velocity is
(a) half of the group velocity (b) equal to the group velocity
(c) greater than group velocity (d) None of the above
Ans: A
82. Choose wrong one :
(a) When central force is repulsive, the orbit is convex to the origin.
(b) If r motion is oscillatory, the orbit is bounded.
(c) For attractive inverse square law, the orbit is circle for E = 0
(d) If the value of eccentricity is equal to one, the shape of the orbit is parabola.
Ans: C
83. In the motion under central force, following remain constant (notations have their usual meaning)
(a) E, p (b) E, l (c) T, p (d) T, l
Ans: B
84. If the Lagrangian is invariant under translation then the following is conserved :
(a) Linear momentum (b) Energy
(c) Angular momentum (d) None of these
Ans: A
85. Generalised force in a system
(a) always has dimensions of force. (b) need not have dimensions of force.
(c) never has dimension of force. (d) None of the above
Ans: B
85. Bose Einstein condensation is observed in system of particles with
(a) half odd integral spin at high temperature
(b) half odd integral spin at very low temperature
(c) integral spin at high temperature
(d) integral spin at very low temperature
Ans: D
87. Fermi Dirac distribution is obeyed by
(a) all atoms and molecules (b) identical classical particles
(c) particles with half odd integral spin (d) particles with integral spin
Ans: C
88. Ten atoms with their magnetic moments +µ and –µ are fixed in a linear lattice. In how
many ways the arrangement results in a magnetic dipole moments equal to 2µ ?
(a) 2 (b) 24 (c) 210 (d) 720
Ans: C
89. In polar regions life of aquatic animals survives because of following property of water
(a) Its density is maximum at 4 °C. (b) Its freezing point is ~ 0 °C.
(c) Its boiling point is ~ 100 °C. (d) None of the above
Ans: A
90. The symbols having their usual meanings, the value of Tds for a thermodynamic system is
(a) Zero (b) pdv (c) Vdp (d) p dTs
Ans: B
91. Which one of the following thermodynamic quantities is not a state function ?
(a) Gibb’s free energy (b) Enthalpy
(c) Entropy (d) Work
Ans: D
91. According to Maxwell’s law of distribution of velocities of molecules, the most probable
velocity is
(a) Greater than the mean velocity (b) Equal to the mean velocity
(c) Equal to the root mean square velocity(d) Less than the root mean square velocity
Ans: D
92. The sum of internal energy (U) and the product of pressure and volume (p, v) is known as
(a) Entropy (b) Enthalpy (c) Work done (d) Heat rejected
Ans: B
93. During a change of phase, the Gibb’s function of a system
(a) increases (b) decreases
(c) remains constant (d) may increase or decrease
Ans: C
(a) total scattering cross-section (b) differential scattering cross-section
(c) scattered angular flux (d) number of fixed scattering centres
Ans: B
50. Particles of energy 9 eV are sent towards a potential step of height 8 eV. The percentage of particles reflected back is
(a) 25% (b) 50%
(c) 75% (d) No particle will be reflected
Ans: A
51. The Yukawa potential is static and spherically symmetric solution to the
(a) Schrödinger equation (b) Dirac equation
(c) Klein-Gordon equation (d) None of the above
Ans: C
52. The magnitude of the linear momentum of a photon in a beam of He-Ne laser having wavelength λ = 634 nm will be in eV/c as :
(a) 1.96 (b) 2.20 (c) 1.80 (d) 1.90
Ans: A
53. The group velocity of matter is
(a)1 less than particle velocity (b) greater than particle velocity
(c) equal to particle velocity (d) same as phase velocity
Ans: C
54. If an oscillator is in its ground state, then the probability of finding the particle outside the classical limits is approximately
(a) 16% (b) 24% (c) 48% (d) 84%
Ans: A
55. Which of the following is its own anti-particle ?
(a) π° (Neutral pion) (b) k° (Neutral kaon)
(c) ∧° (Neutral Lambda Hyperon) (d) N (Neutron)
Ans: A
56. Deviation of a nuclear charge distribution from spherical symmetry defines :
(a) Its spin angular momentum (b) Its electric dipole moment
(c) Its electric quadrupole moment (d) The monopole moment
Ans: C
57. The Baryon number is 1 for
(a) Proton (b) µ-meson
(c) π-meson (d) Lepton
Ans: A
58. Σ-baryons exist in three charged states -1, 0 and + 1. It has strangeness (s) :
(a) – 2 (b) – 1 (c) 1 (d) 0
Ans: B
59. A gamma-ray photon creates an electron – positron pair. If the rest mass of electron is 0.5 MeV and total kinetic energy of the pair is 0.78 MeV, the energy of gamma-ray must be
(a) 0.28 MeV (b) 1.28 MeV (c) 1.78 MeV (d) 0.78 MeV
Ans: C
60. Which one of the following statements is true that nuclear forces are
(a) Long range forces (b) Central forces
(c) Exchange forces (d) Unsaturated forces
Ans: C
61. In a Vande Graff accelerator, ion source injects proton in the accelerating tube in the high voltage dome. 7 MV potential is applied to the dome. The kinetic energy of the proton after acceleration will be
(a) 14 MeV (b) 9.5 MeV (c) 8.4 MeV (d) 7 MeV
Ans: D
62. A nucleus will disintegrate into parts if the mass defect relative to these parts is
(a) Positive (b) Negative
(c) Zero (d) Both Positive and Negative
Ans: A
63. Atomic nuclei with same number of neutrons or protons equal to magic numbers, are exceptionally
(a) low Z-nuclei (b) radioactive in nature
(c) stable (d) weak
Ans: C
64. When electromagnetic wave passes from one medium to another, the boundary condition is
(a) normal component of electric field vector is continuous.
(b) normal component of magnetic field vector is continuous.
(c) parallel component of electric field vector is not continuous.
(d) parallel component of magnetic field vector is continuous.
Ans: B
65. A point charge q is placed at a distance d from an earthed conducting sphere (initially uncharged) of radius R(R < d). Now earthing is removed and then charge q is moved to infinite. Charge on the sphere now will be
(a) zero (b) q/2
(c) – qR/d (d) None of the above
Ans: C
66. Fine structure of Hydrogen α-line is explained by
(a) Bohr atom model
(b) Rutherford atom model
(c) Spin orbit interaction combined with relativistic correction
(d) Sommerfeld elliptical method with relativistic correction and spin of electron.
Ans: D
67. The quantum of Lattice vibration is known as a
(a) photon (b) phonon (c) Graviton (d) Gluon
Ans: B
68. When a magnetic material is subjected to an external magnetizing field, its ability to get
magnetized is described in terms of
(a) Magnetic permeability (b) Magnetic susceptibility
(c) Magnetic viscosity (d) Magnetic resonance
Ans: B
69. The quartz crystal is an example of
(a) A negative uniaxial crystal (b) A positive uniaxial crystal
(c) A biaxial crystal (d) None of the above
Ans: B
70. The super conductors are
(a) Perfect ferromagnetics (b) Perfect paramagnetics
(c) Perfect diamagnetics (d) perfect anti-ferromagnetics
Ans: C
71. A crystal system whose unit cell is specified by a = b ≠ c, α = β = γ = 90° (where a, b, c
and α, β, γ have their usual meaning) is known as
(a) Monoclinic (b) Orthorhombic
(c) Tetragonal (d) Rhombohedral
Ans: C
72. In any radio receiver, the active device used for demodulation is
(a Triode (b) Tetrode (c) Pentode (d) Diode
Ans: D
73. The hexadecimal number 3C is equivalent to decimal number
(a) 60 (b) 40 (c) 20 (d) 85
Ans: A
74. Which one of the following is not a basic logic gate ?
(a) OR (b) AND (c) XOR (d) NOT
Ans: C
75. Bubbled (inverted) inputs OR gate is equivalent to a
(a) NOR gate (b) NAND gate (c) XNOR gate (d) XOR gate
Ans: B
76. Mobility of charge carrier is
(a) Velocity per unit applied voltage (b) Velocity per unit applied electric field
(c) Velocity per unit current (d) Variation of velocity with temperature
Ans: B
77. Indicate the false statement from the following statements for a Zener diode whose breakdown voltage is 4.7 volts :
(a) Zener diode is constructed from heavily doped material.
(b) Breakdown occurs due to collision of high velocity minority carrier.
(c) Breakdown is due to high electric field across the depletion region.
(d) Tunnelling of minority carrier through the junction.
Ans: B
78. Which type of negative feedback is used in a buffer amplifier ?
(a) Voltage series (b) Current series
(c) Voltage shunt (d) Current shunt
Ans: A
79. If we apply AC voltage V = Vp sin ωt at the input of a half wave rectifier then the output DC voltage without using any filter in circuit is
(a) Vp/π (b) 2 Vp/π (c) Vp/2π (d) Vp/2
Ans: A
80. When a rigid body rotates about a given axis, the degrees of freedom associated with it will be
(a) 1 (b) 3 (c) 2 (d) 4
Ans: A
81. For a non-relativistic free particles the phase velocity is
(a) half of the group velocity (b) equal to the group velocity
(c) greater than group velocity (d) None of the above
Ans: A
82. Choose wrong one :
(a) When central force is repulsive, the orbit is convex to the origin.
(b) If r motion is oscillatory, the orbit is bounded.
(c) For attractive inverse square law, the orbit is circle for E = 0
(d) If the value of eccentricity is equal to one, the shape of the orbit is parabola.
Ans: C
83. In the motion under central force, following remain constant (notations have their usual meaning)
(a) E, p (b) E, l (c) T, p (d) T, l
Ans: B
84. If the Lagrangian is invariant under translation then the following is conserved :
(a) Linear momentum (b) Energy
(c) Angular momentum (d) None of these
Ans: A
85. Generalised force in a system
(a) always has dimensions of force. (b) need not have dimensions of force.
(c) never has dimension of force. (d) None of the above
Ans: B
85. Bose Einstein condensation is observed in system of particles with
(a) half odd integral spin at high temperature
(b) half odd integral spin at very low temperature
(c) integral spin at high temperature
(d) integral spin at very low temperature
Ans: D
87. Fermi Dirac distribution is obeyed by
(a) all atoms and molecules (b) identical classical particles
(c) particles with half odd integral spin (d) particles with integral spin
Ans: C
88. Ten atoms with their magnetic moments +µ and –µ are fixed in a linear lattice. In how
many ways the arrangement results in a magnetic dipole moments equal to 2µ ?
(a) 2 (b) 24 (c) 210 (d) 720
Ans: C
89. In polar regions life of aquatic animals survives because of following property of water
(a) Its density is maximum at 4 °C. (b) Its freezing point is ~ 0 °C.
(c) Its boiling point is ~ 100 °C. (d) None of the above
Ans: A
90. The symbols having their usual meanings, the value of Tds for a thermodynamic system is
(a) Zero (b) pdv (c) Vdp (d) p dTs
Ans: B
91. Which one of the following thermodynamic quantities is not a state function ?
(a) Gibb’s free energy (b) Enthalpy
(c) Entropy (d) Work
Ans: D
91. According to Maxwell’s law of distribution of velocities of molecules, the most probable
velocity is
(a) Greater than the mean velocity (b) Equal to the mean velocity
(c) Equal to the root mean square velocity(d) Less than the root mean square velocity
Ans: D
92. The sum of internal energy (U) and the product of pressure and volume (p, v) is known as
(a) Entropy (b) Enthalpy (c) Work done (d) Heat rejected
Ans: B
93. During a change of phase, the Gibb’s function of a system
(a) increases (b) decreases
(c) remains constant (d) may increase or decrease
Ans: C
94. A window is made up of a square portion and an equilateral triangle portion above it. The base of the triangular portion coincides with the upper side of the square. If the perimeter of the window is 6 m, the area of the window in m2 is ___________.
(A) 1.43
(B) 2.06
(C) 2.68
(D) 2.88
Ans: B
95. Carbon, silicon and germanium atoms have four valence electrons each. Their valence and conduction bands are separated by energy band gaps represented by (Eg)C, (Eg)Si and (Eg)Ge respectively. Which one of the following relationships is true in their case ?
1) (Eg)C > (Eg)Si
2) (Eg)C = (Eg)Si
3) (Eg)C < (Eg)Ge
4) (Eg)C < (Eg)Si
Ans: 1
96. If λ v, λ x andλ m represent the wavelengths of visible light, X-rays and microwaves respectively, then :
1) λm > λx > λv
2) λv > λm > λx
3) λm > λv > λx
4) λv > λx > λm
Ans: 3
97. Two boys are standing at the ends A and B of a ground, where AB = a. The boy at B starts running in a direction perpendicular to AB with velocity v1. The boy at A starts running simultaneously with velocity v and catches the other boy in a time t, where t is :
1) a/√(v2 + v21)
2) √(a/v2 - v21)
3) a/(v - v1)
4) a/(v + v1)
Ans: 2
98. A 5-A fuse wire can withstand a maximum power of 1 W in circuit. The resistance of the fuse wire is :
1) 0.02 Ω
2) 0.2 Ω
3) 0.4 Ω
4) 0.04 Ω
Ans: 4
99. Two bodies have their moments of inertia I and 2I respectively about their axis of rotation. If their kinetic energies of rotation are equal, their angular momenta will be in the ratio :
1) 1 : 4
2) √2 : 1
3) 4 : 1
4) 1 : √2
Ans: 4
100. An electron moves in a circular orbit with a uniform speed v. It produces a magnetic field B at the centre of the circle. The radius of the circle is proportional to :
1) B/v
2) v/B
3) √(v/B)
4) √(B/v)
Ans: 3
(A) 1.43
(B) 2.06
(C) 2.68
(D) 2.88
Ans: B
95. Carbon, silicon and germanium atoms have four valence electrons each. Their valence and conduction bands are separated by energy band gaps represented by (Eg)C, (Eg)Si and (Eg)Ge respectively. Which one of the following relationships is true in their case ?
1) (Eg)C > (Eg)Si
2) (Eg)C = (Eg)Si
3) (Eg)C < (Eg)Ge
4) (Eg)C < (Eg)Si
Ans: 1
96. If λ v, λ x andλ m represent the wavelengths of visible light, X-rays and microwaves respectively, then :
1) λm > λx > λv
2) λv > λm > λx
3) λm > λv > λx
4) λv > λx > λm
Ans: 3
97. Two boys are standing at the ends A and B of a ground, where AB = a. The boy at B starts running in a direction perpendicular to AB with velocity v1. The boy at A starts running simultaneously with velocity v and catches the other boy in a time t, where t is :
1) a/√(v2 + v21)
2) √(a/v2 - v21)
3) a/(v - v1)
4) a/(v + v1)
Ans: 2
98. A 5-A fuse wire can withstand a maximum power of 1 W in circuit. The resistance of the fuse wire is :
1) 0.02 Ω
2) 0.2 Ω
3) 0.4 Ω
4) 0.04 Ω
Ans: 4
99. Two bodies have their moments of inertia I and 2I respectively about their axis of rotation. If their kinetic energies of rotation are equal, their angular momenta will be in the ratio :
1) 1 : 4
2) √2 : 1
3) 4 : 1
4) 1 : √2
Ans: 4
100. An electron moves in a circular orbit with a uniform speed v. It produces a magnetic field B at the centre of the circle. The radius of the circle is proportional to :
1) B/v
2) v/B
3) √(v/B)
4) √(B/v)
Ans: 3