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Sunday, 26 June 2016

FSc ICS MCAT ECAT Physics Second Year Chapter 21 Nuclear Physics Multiple Choice Question (MCQ) Notes

FSc ICS MCAT ECAT Physics Second Year Chapter 21 Nuclear Physics Multiple Choice Question (MCQ) Notes

Both Bold and Underlined option is correct


1. The term "dead time" in G.M counter means the time of the order of:
  • More than 1 millisecond
  • Less than 1 millisecond
  • More than 1 micro sec
  • None of these

2. In solid state detector, the reverse bias is applied through the two:
  • Conducting layers of silver
  • Conducting layers of gold
  • Conducting layers of aluminium
  • Conducting layers of plastic

3. In solid state detector, the energy needed to produce an electron hole pair is about:
  • 3 MeV to 4 MeV
  • 3 eV to 4 eV
  • Both above options
  • None of these

4. The phenomenon of nuclear fission is used in the construction of:
  • Atomic bombs
  • Hydrogen bomb
  • Both above options
  • None of these

5. In fission reactor, heavy water is used as:
  • Heat exchanger
  • Coolant
  • Moderator
  • None of these

6. The Wilson cloud chamber is based on the principle that supper saturated vapours condense more readily on:
  • Ions and dust particles
  • Dust particles
  • Ions
  • None of these

7. Wilson cloud chamber is a device used as:
  • Path of ionizing particle
  • Accelerating positively charged particle
  • Accelerating negatively charged particle
  • None of these

8. In Wilson Cloud chamber, the Alpha particle leave:
  • Thin and discontinuous tracks
  • No tracks
  • Thick, straight and continuous tracks
  • None of these

9. Geiger counter was designed by:
  • Mosley
  • Michelson
  • Geiger and Muller
  • Faraday

10. Geiger Muller counter is suitable for:
  • Slow counting
  • Fast counting
  • Both options above
  • None of these

11. Specially designed solid state detector can be used to detect:
  • Gamma rays
  • X rays
  • Alpha particles
  • Beta particles

12. A solid state detector is basically:
  • A p-n-p transistor
  • A n-p-n transistor
  • A reverse p-n junction
  • A forward p-n junction

13. The potential difference between the top and bottom of a cloud chamber is of the order of:
  • 290 V
  • 400 V
  • 1 KV
  • None of these

14. The potential difference between anode and cathode in a neon-bromine filled G.M counter is:
  • 290 V
  • 400 V
  • 1 KV
  • 2 MV

15. Which one of the following detectors can count fast and operate at low voltage:
  • Solid state detector
  • G.M counter
  • Wilson cloud detector
  • None of these

16. In G.M counter, the positive ions take time to reach the cathode is:
  • 10(-2) s
  • 10(-3) s
  • 10(-4) s
  • 10(-6) s

17. The capture of a neutron by a nucleus results in the formation of:
  • Deutron
  • Proton
  • Helium
  • Radio isotope

18. Atomic mass scale 1u is equal to:
  • 1.66 * 10(18) kg
  • 1.66 * 10(-19) kg
  • 1.66 * 10(-27) kg
  • 1.66 * 10(27) kg

19. One joule of energy absorbed per kilogram of a body is:
  • Roentgen
  • Grey
  • Rem
  • Curie

20. The total energy transferred to a body by means of radiation is measured in units of:
  • Becquerels
  • Grey
  • Rem
  • Roentgen

21. The SI unit of radiation dose is:
  • Roentgen
  • Curie
  • Grey
  • Rem

22. The number of fundamental forces present in nature are:
  • 3
  • 2
  • 5
  • 4

23. During fusion of hydrogen into helium:
  • Energy is released
  • Energy is absorbed
  • Mass is increased due to energy absorption
  • Mass is reduced due to energy released

24. The mass spectrograph of naturally occurring neon, showing:
  • 1 isotope
  • 2 isotope
  • 3 isotope
  • 4 isotope

25. X rays and γ rays of the same energy may be distinguished by:
  • their velocity
  • their ionizing power
  • their intensity
  • method of production

26. Which of the following is not  a mode of radioactive?
  • Electron emission
  • Alpha decay
  • Proton emission
  • Ionized hydrogen atom

27. The wavelength of γ rays ( in meter is of the order of):
  • 10(-7)
  • 10(-10
  • 10(-12)
  • 10(-15)

28. After 2 hours (1/16)th of the initial amount of a certain radioactive isotope remains undecayed. The half-life of the isotope is:
  • 60 minutes
  • 45 minutes
  • 30 minutes
  • 15 minutes

29. When Uranium 238U92 decays to lead 206Pb82, the number of alpha particles and beta particles emitted are:
  • 6 and 6 respectively
  • 8 and 8 respectively
  • 6 and 8 respectively
  • 8 and 6 respectively

30. The unit of radioactivity is:
  • Curie
  • Rutherford
  • Both first and second
  • None of these

31. Half life of a radioactive element depends upon:
  • Amount of the element present
  • Temperature
  • Pressure
  • None of the above

32. The nuclei 13C6 and 14N7 can be described as:
  • Isotones
  • Isobars
  • Isotopes of carbon
  • Isotopes of nitrogen

33. The rate of decay of a radioactive element:
  • is constant
  • Decreases inversely with time
  • Increases directly with time
  • Decreases exponentially

34. A radioactive substance has a half life of four months. Three-fourths of the substance will decay in:
  • Three months
  • Four months
  • Eight months
  • Twelve months

35. Particles which can be added to the nucleus of an atom without changing its chemical properties are called:
  • Neutrons electrons
  • Electrons
  • Protons
  • Alpha particles

36. Nuclear reactions, we have the conversation of:
  • Mass
  • Energy only
  • Momentum only
  • Mass, energy and momentum

37. Atoms having equal number of neutrons as well as equal number of protons but with nucleons in different energy states are called:
  • Isotopes
  • Isobars
  • Isotones
  • Isomers

38. If the matter in proton is completely converted into energy, it will be about:
  • 9310 MeV
  • 100.78 MeV
  • 931 MeV
  • 10078 MeV

39. One atomic mass unit is equal to:
  • 1/12 mass of one C atom
  • 1/16 mass of O2 molecule
  • 1/14 mass of N2 molecule
  •  1/9 mass of F2 molecule

40. The mass number of He is 4 that for sulphur is 32. The radius of sulphur nucleus is larger than that of helium by times:
  • √8
  • 4
  • 2
  • 8

41. For nuclear forces to be effective, the distance should be:
  • 10(-10) m
  • 10(-13) m
  • 10(-15) m
  • 10(-20) m

42. What was the fissionable material used in the bomb dropped at Nagasaki (Japan) in the year 1945?
  • Uranium
  • Neptunium
  • Berkelium
  • Plutonium

43. Which of the following uranium atoms undergo fission readily?
  • 238U
  • 237U
  • 236U
  • 235U

44. Control rods used in nuclear reactors are made of:
  • Stainless steel
  • Graphite
  • Cadmium
  • Plutonium

45. One atomic mass unit is equal to:
  • 1.67 * 10(-27) pound mass
  • 1.67 * 10(-27) slug
  • 1.67 * 10(-27) kg
  • 1.67 * 10(-27) g

46. Nuclei having the same nuclear mass but different nuclear charge are called:
  • Isotones
  • Isomers
  • Isobars
  • Isotopes

47. One particle having zero mass and zero charge, which is emitted with beta decay, is called:
  • Positron
  • Electron
  • Neutrino
  • Neutron

48. The rate of decay (disintegration per unit time) of a radioactive substance:
  • is constant
  • Decreases exponentially with time
  • Varies inversely as time
  • Decreases linearly with time

49. The binding energy per nucleon is:
  • Greatest for heavy nuclei
  • Least for heavy nuclei
  • Greatest for light nuclei
  • Greatest for medium weight nuclei

50. Controlled fission reactions are maintained in a:
  • Cyclotron
  • Linear accelerator
  • Nuclear reactor
  • Stellerator

51. Alpha particle are highly ionizing because of:
  • their high charge and low speeds
  • their greater mass
  • their larger energy
  • their constituents

52. A radioactive decay rate of 3.7 * 10(10) disintegrates per second defines the unit of measurement known as the:
  • Rutherford
  • Rontgen
  • Curies
  • Becquerel

53. The total energy transferred to a body by means of radiation is measured in units of:
  • Rutherfords
  • Rontgens
  • Curies
  • Becquerels

54. Which of the following radiations are suitable for the treatments of flesh just under skin?
  • Alpha radiations
  • Beta radiations
  • Gamma radiations
  • X-rays

55. Fraction of decaying atoms per unit time is:
  • Decay constant
  • Life-time
  • Half-life
  • None

56. SI unit of radiation dose is:
  • Becquerel
  • Curie
  • Gray
  • All

57. Disintegration of nucleus obeys the laws of conservation of:
  • Charge only
  • Mass only
  • Both charge & mass
  • None of above

58. The nuclear fission reaction is the practical example of an:
  • Exothermic reaction
  • Endothermic reaction
  • Chemical reaction
  • All of above

59. The quantity called absorbed radiation dose 'D' is defined by:
  • E / m
  • E / C
  • m / c
  • C / E

60. The γ-rays radiographs are used in:
  • Agricultural industry
  • Medical industry
  • Support industry
  • All of above

61. Subatomic particles are divided into:
  • Two groups
  • Three groups
  • Four groups
  • Infinite groups

62. The lightest element which exhibits radioactivity is:
  • Hydrogen
  • Deuteron
  • Tritium
  • Helium

63. In radioactive element, β-ray emit from:
Nucleus
Outer orbit
Inner orbit
None of these

64. Which one of the following statements is true of both α-particles and X-rays?
They cause ionization of the air when they pass through it
They can be detected after passing through a few millimeters of aluminium
They can be deflected by electric fields
They can be deflected be magnetic fields

65. The radiation having maximum penetration power is:
  • X-rays
  • γ-rays
  • α-rays
  • Cathode rays

66. Heavy radioactive elements eventually turn into:
  • Barium
  • Hydrogen
  • Lead
  • Radium

67. Emission of β-rays in a radioactive decay results in a daughter element showing a:
  • Change in mass but not in charge
  • Change in charge but not in mass
  • Change in both
  • Change in neither

68. A radioactive element zXa emits an α-particle and changes into:
  • z-2Ya
  • zYa-4
  • z-2Ya-4
  • z+2Ya

69. When a β-particle is emitted from nucleus, the effect on its neutron-proton ratio is:
  • Increased
  • Decreased
  • Remains same
  • Increases and then decreases

70. What is curie?
  • Measurement of radioactivity
  • Measurement of temperature
  • Measurement of magnetism
  • Measurement of electric field

71. The mother and daughter elements, with the emission of γ-rays, are called:
  • Isotopes
  • Isobars
  • Isomers
  • Isodiaphers

72. The average life (T) and the decay constant λof the radioactive nucleus are related as:
  • Tλ = 1
  • T = 0.693 / λ
  • T / λ = 1
  • T = c / λ

73. A nucleus with an excess of neutrons may decay radioactively with the emission of:
  • A neutron
  • A proton
  • An electron
  • A positron

74. The penetrating power of X-rays increases with:
  • Decrease in their velocity
  • Increase in their velocity
  • Increase in their intensity
  • Decrease in their intensity

75. Such type of radiation which can burn human skin is called:
  • Far-infrared
  • Infrared
  • Ultra-violet
  • Microwaves

76. Nuclear force is:
  • Attractive and long range force
  • Repulsive and long range force
  • Attractive and short range force
  • Repulsive and short range force

77. Mass defect per nucleon is called:
  • Binding energy of nucleus
  • Packing fraction
  • Average energy of nucleus
  • Average energy of reaction

78. The binding energy of Deutron is:
  • 22.24 MeV
  • 2.224 MeV
  • 0.224 MeV
  • 222.4 MeV

79. The reciprocal of decay constant (λ) of a radioactive element is:
  • Half life
  • Mean life
  • Total life
  • Curie

80. The half-life of a radioactive element depends on:
  • Temperature
  • Pressure
  • Nature of element
  • Amount of radioactive substance

81. The radioactive decay obeys the law:
  • No = N(1 + e(λt))
  • N = Noe(λt)
  • N = Noe(-λt)
  • No = Ne(-λt)

82. Energy liberated when one atom of 235U92 undergoes fission reaction is:
  • 140 MeV
  • 28 MeV
  • 200 MeV
  • 60 MeV 

83. The moderator used in a nuclear reactor is:
  • Aluminium
  • Sodium
  • Calcium
  • Graphite

84. The range of 7.7 MeV α-particle in air is about:
  • 10 cm
  • 20 cm
  • 17 cm
  • 7 cm

85. A 3MeV β-particle can penetrate through an aluminium foil about:
  • 65 mm
  • 0.65 mm
  • 6.5 mm
  • 0.065 mm

86. Geiger Muller counter always uses:
  • Argon and alcohol
  • Bromine mixed with neon
  • Different gases at different pressures
  • Argon only

87. The maximum safe limit does person working in nuclear power station is:
  • 0.1 rem per week
  • 4 rem per week
  • 5 rem per week
  • 3 rem per week

88. The most useful tracer is:
  • Iodine-131
  • Strontium-90
  • Carbon-14
  • Cobalt-60

89. One joule of energy absorbed per kilogram of body is:
  • Rem
  • Roentgens
  • Grey
  • Becquerel

90. The types of quarks are:
  • 2
  • 3
  • 4
  • 6

91. The strong nuclear force acts on the:
  • Mesons only
  • π-mesons only
  • Photons only
  • Hadrons only

92. Which one of the following belongs to Leptons group?
  • Electrons
  • Neutrino
  • Muons
  • All of them

Written by: Asad Hussain 

Thursday, 23 June 2016

FSc ICS MCAT ECAT Physics First Year Chapter 3 Motion and Force Multiple Choice Question (MCQ) Notes

FSc ICS MCAT ECAT Physics First Year Chapter 3 Motion and Force Multiple Choice Question (MCQ) Notes

Both Bold and Underlined option is correct


1. With the help of velocity-time graph, we can find:

  • Distance
  • Time
  • Velocity
  • Momentum


2. The area under the curve of velocity-time graph gives:

  • Acceleration
  • Velocity
  • Distance
  • Direction


3. If a body is moving with constant velocity of 20 m/s towards North then its acceleration is"

  • 5 m/s(2)
  • 9 m/s(2)
  • 10 m/s(2)
  • Zero


4. The laws of motion shows the relation between:

  • Distance and velocity
  • Displacement and velocity
  • Mass and velocity
  • Force and acceleration


5. Inertia of a body is measured in terms of its:

  • Weight
  • Force
  • Mass
  • Acceleration


6. A force of 100 N acts on a body for 5 seconds, what will be the change in momentum:

  • 20 Ns
  • 500 Ns
  • 100 Ns
  • 1000 Ns


7. Velocity of the projectile at the maximum height attained when projected with velocity vi is:
  • vx = vi sinθ
  • vh = vi cosθ
  • Zero
  • vi

8. A body is falling freely strikes the ground in 5 seconds, distance covered by it in 5 second is:
  • 122.5 m
  • 25 m
  • 24.5 m
  • 34.5 m

9. The total time for which the projectile remains in air is called:
  • Time of projectile
  • Time period
  • Time of flight
  • Time constant

10. The angle of projection to cover maximum horizontal range is:
  • 90
  • 120
  • 18
  • 45

11. The ballistic missiles are useful only for:
  • Long range
  • Vertical range
  • Short range
  • Normal range

12. When there is no loss of K.E and momentum then the collision is called:
  • Elastic collision
  • In-elastic collision
  • Inertial collision
  • None of these

13. The horizontal component of a projectile moving with initial velocity 200 m/s at an angle of 60 to x-axis is:
  • 100 m/s
  • 250 m/s
  • 50 m/s
  • 200 m/s

14. A ball is dropped from a height of 4.2 meters. To what height will it rise of there is no loss of K.E. after rebounding?
  • 4.2 m
  • 8.4 m
  • 12.6 m
  • None of these

15. The dimension of linear inertia is:
  • MLT(2)
  • ML(0)T(-2)
  • ML(0)T(0)
  • MLT(-1)

16. A body of mass 5 kg is acted upon by a constant force of 20 N for 7 seconds. The total change in momentum will be:
  • 10 Ns
  • 100 Ns
  • 140 Ns
  • 200 Ns

17. The magnitude of the force producing an acceleration of 10 m/s(2) in a body of mass 0.5 kg is:
  • 3 N
  • 4 N
  • 5 N
  • 6 N

18. A certain force gives an acceleration of 4m/s(2) to a body of mass 10 kg. The same force would give a 20 kg object an acceleration of:
  • 0.5 m/s(2)
  • 2.0 m/s(2)
  • 1.5 m/s(2)
  • 9.8 m/s(2)

19. One newton is a force that produces an acceleration of 5 m/s(2) in a body of mass:
  • 0.2 kg
  • 3 kg
  • 4 kg
  • 8 kg

20. A body is thrown vertically upward with initial velocity of 19.6 m/s. It will reach the height of:
  • 49.2 m
  • 29.4 m
  • 9.8 m
  • 4.9 m

21. If the acceleration of a body is negative, then slope of the velocity-time graph will be:
  • Zero
  • Positive
  • Negative
  • Infinity

22. Acceleration of 2.5 m/s(2) expressed in km/hr(2) is:
  • 324
  • 5.4
  • 5400
  • 32400

23. A body starting from rest covers a distance of 45 km and acquires a velocity of 100 km/hr. Its acceleration will be:
  • 0.092 m/s(2)
  • 0.8 m/s(2)
  • 7.71 m/s(2)
  • 0.15 m/s(2)

24. A force of 50 N acts on a body for 0.01 sec and changes its velocity from 5 m/s to 10 m/s/. The amount of impulse will be:
  • 100 Ns
  • 250 Ns
  • 10 Ns
  • 5 Ns

25. Two fast moving vehicles suffer head-on collision with a force of 1000 N for an interval of 10(-1) seconds. The impulse is:
  • 10(-1) Ns
  • 1 Ns
  • 10(-3) Ns
  • 10(5) Ns

26. Range of the projectile is the same for the following pair of angles:
  • 0 and 45
  • 35 and 55
  • 15 and 60
  • 30 and 75

27. A body is moving with a velocity v in the east direction. If it travels with the same velocity in the north direction, then resultant velocity is:
  • v
  • 2v
  • v/(2)
  • (2v)

28. If displacement of a particle is zero, the distance covered:
  • must be zero
  • may or may not be zero
  • cannot be zero
  • depends upon the particle

29. A body moves 4 m towards east and then 3 m north. The displacement and distance covered by the body are:
  • 7m, 6m
  • 6m, 5m
  • 5m, 7m
  • 4m, 3m

30. A moving body is covering the distance directly proportional to the square of the time. The acceleration of the body is:
  • Increasing
  • Decreasing
  • Zero
  • Constant

31. A body covered a distance of 5 m along a semicircular path. The ratio of distance to displacement is:
  • 11 : 7
  • 12 : 5
  • 8 : 3
  • 7 : 5

32. Which of the following changes when a particle is moving with uniform velocity:
  • Speed
  • Velocity
  • Acceleration
  • Position vector

33. If R is the maximum horizontal range of a particle, then the greatest height attained by it is:
  • R
  • 2R
  • R / 2
  • R / 4

34. A stone is just released from the window of a train moving along a horizontal straight track. The stone will hit the ground following a:
  • Straight line path
  • Circular path
  • Parabolic path
  • Hyperbolic path

35. If the time of flight of a projectile is doubled, what happens to the maximum height attained?
  • Halved
  • Remains unchanged
  • Doubled
  • Becomes four times

36. A 10 N force is applied on a body which produces in it an acceleration of 1 m/s(2). The mass of the body is:
  • 10 kg
  • 5 kg
  • 15 kg
  • 20 kg

37. Which of the following change when a particle is moving with uniform velocity:
  • Speed
  • Velocity
  • Acceleration
  • Position vector

38. The numerical ratio of velocity to speed is:
  • Less than 1
  • Less than 0
  • Greater than 1
  • Either less than or equal to one

39. A moving particle finally comes to rest. What will be the angle between acceleration and displacement during motion?
  • π / 2
  • π / 4
  • π
  • 0

40. The gradient of the velocity time graph represents:
  • Speed
  • Acceleration
  • Distance
  • Velocity

41. A body of 2 kg moves with an acceleration of 20 m/s. Its rate of change of momentum is:
  • 10 kgm/s(2)
  • 20 kgm/s(2)
  • 40 kgm/s(2)
  • 400 kgm/s(2)

42. A bullet of mass 'm' is fired with a velocity V into a block mass M and sticks to it. The final velocity of the system is:
  • mV / M
  • mV / (m + M)
  • MV / m
  • (m+M)V / m

43. A projectile is thrown at an angle of 45 with horizontal. If K is the K.E with which the projectile was thrown, then the K.E at the top of the trajectory is:
  • 2K
  • 4K
  • K / 2
  • K / 4

44. At the top of the trajectory of a projectile, the direction of its velocity and acceleration and:
  • Perpendicular to each other
  • Parallel to each other
  • Inclined at an angle 45 of to the horizontal
  • None of the above is correct

45. A ball weight 0.5 N is thrown vertically upward. The ball returns to the ground in 4s, then the impulse of the ball is:
  • 1 Ns
  • 2 Ns
  • 4 Ns
  • 20 Ns

46. If m is the mass of the gases ejected per second with velocity v relative to the rocket of mass M, then the up thrust acting on the rocket is:
  • mv
  • mv / M
  • Mv / m
  • Mmv

47. A projectile will cover same horizontal distance when the initial angles of projection are:
  • 20, 60
  • 20, 50
  • 20, 40
  • 20, 70

48. At what angle with horizontal should a ball be thrown so that its range R is related to the time of flight as R = 5 T(2) (Take g = 10 m/s(2))
  • 30
  • 45
  • 60
  • 90

49. During projectile motion, the quantities that remains unchanged are:
  • Force and vertical velocity
  • Acceleration and horizontal velocity
  • Kinetic energy and acceleration
  • Acceleration and momentum

50. A trolley runs down a slope from rest with constant acceleration. In the first second, it travels 1.6 m. its acceleration is:
  • 0.8 m/s(2)
  • 1.6 m/s(2)
  • 3.2 m/s(2)
  • 6.4 m/s(2)

51. There are three Newton's laws of motion. We can drive:
  • Second and third from first law
  • Third and first laws from second
  • First and second from third law
  • All laws are independent of each other

52. A shell in flight explodes into four unequal parts. Which of the following is given by:
  • Momentum and K.E
  • Momentum and total energy
  • K.E
  • Neither momentum nor K.E

53. The acceleration of a body sliding down a smooth inclined plane is given by:
  • g sinθ
  • μ cosθ
  • g(sinθ + μ cosθ)
  • g(sinθ - μ cosθ)

54. The string of a vibrating pendulum is cut when it is at extreme position. The bob will follow a:
  • Vertical path
  • Horizontal path
  • Parabolic path
  • Circular path

55. The numerical value of the ratio of displacement to distance is:
  • Always less than one
  • Always equal to one
  • Always more than one
  • Equal to or less than one

56. Two bodies are projected at angle 'angle' and (90-angle) to the horizontal with the same speed the ratio of their times of flight T1 / T2 is:
  • 1 : 1
  • 1 : tanθ
  • tanθ : 1
  • None of these

57. The magnitude of a average velocity is equal to the average speed when a particle moves:
  • on a curve path
  • in the same direction
  • with constant acceleration
  • with constant retardation

58. A body is imparted motion from rest to move in a straight line. It is then obstructed by an opposite force, then:
  • the body may necessarily change direction
  • the body is sure to slow down
  • the body will necessarily continue to move in the same direction at the same speed
  • none of the above

59. The distance traveled by a body falling freely from rest in the first, second and third seconds are in the ratio:
  • 1 : 2 : 3
  • 1 : 3 : 5
  • 1 : 4 : 9
  • None of these

60. Which of the following four statements is false?
  • A body can have zero velocity and still be accelerated
  • A body can have a constant velocity and still have a varying speed
  • A body can have a constant speed and still have a varying velocity
  • The direction of the velocity of a body can change when its acceleration is constant

61. If an iron ball and a wooden ball of the same radius are released from a height h in a vacuum, then time taken by both of them to reach ground will be:
  • Unequal
  • Exactly equal
  • Roughly equal
  • Zero

62. The angle between instantaneous displacement and acceleration during the retarded motion is:
  • 180
  • 40
  • 45
  • 0

63. A fighter plane is chasing another plane, when it opens fire its speed.
  • Increases
  • Decreases
  • Remains same
  • It stops

64. During the projectile motion, the horizontal component of velocity.
  • Changes with time
  • Becomes zero
  • Remains constant
  • Increase with time

65. Newton's first law of motion gives definition of:
  • Mass
  • Force
  • Acceleration
  • Speed

66. The acceleration of projectile at the highest point is:
  • Zero
  • Increases
  • Decreases
  • Constant

67. Change of momentum is called:
  • Force
  • Pressure
  • Impulse
  • Tension

68. For a projectile, the ratio of maximum height reached to the square of flight time is:
  • 5 : 4
  • 5 : 2
  • 5 : 1
  • 10 : 1

69. A body is dropped from a tower with zero velocity reaches ground in 4 seconds. The height of the tower is about:
  • 80 m
  • 20 m
  • 160 m
  • 40 m

70. A cricket ball is hit so that it travels straight up in air and it can acquires 3 seconds to reach the maximum height. Its initial velocity is:
  • 10 m/s
  • 15 m/s
  • 29.4 m/s
  • 12.2 m/s

Written by: Asad Hussain

Monday, 20 June 2016

FSc ICS MCAT ECAT Physics First Year Chapter 1 Measurements Multiple Choice Question (MCQ) Notes

FSc ICS MCAT ECAT Physics First Year Chapter 1 Measurements Multiple Choice Question(MCQ) Notes

Both Bold and Underlined option is correct

1. The branch of physics "wave mechanic"introduced by:
  • Einstein
  • Max Plank
  • De-broglie
  • Bohr

2. Physicists started believing that every thing about physics has been discovered by the end of:
  • 20 th century
  • 19 th century
  • 15 th century
  • None of these

3. Pascal is famous for his work:
  • Hydrostatics
  • Hydrodynamics
  • Laws of gases
  • Behaviour of elastic bodies

4. Systems international (SI) was established in:
  • 1960
  • 1967
  • 1971
  • 1930

5. The basic quantity among following is:
  • Torque
  • Force
  • Mass
  • Velocity

6. Which one of the scientist made some contribution to geometrical optics:
  • Archimedes
  • Pythagoras
  • Euclid
  • Plato

7. Which of the following is the derived quantity:
  • Time
  • Area
  • Length
  • Mass

8. Which of the following is set of supplementary units:
  • Radian & kilogram
  • Steradian & time
  • Mole & radian
  • Radian & steradian

9. The SI unit for measuring plane angle is:
  • Radian
  • Steradian
  • Both first and second
  • None of these

10. The present standard meter is defined as:
  • The distance between  two points on an alloy bar
  • The length of mean solar day
  • The length equal to 1650763.73 wavelength of krypton 86-atom
  • The distance travel by the light in vacuum during a time of 1/299792458 second

11. The system international (SI) built up from:
  • Derived units
  • Basic units
  • Supplementary units
  • All of these

12. One mile is equal to:
  • 1.625 km
  • 1.609 km
  • 1.325 km
  • 1.850 km

13. One inch is equal to:
  • 1.32 cm
  • 25.4 cm
  • 2.10 cm
  • 2.54 cm

14. One foot is equal to:
  • 31.90 cm
  • 30.84 cm
  • 30.48 cm
  • 84.30 cm

15. Number of nano second in a year is:
  • 3.1536 * 10(7)
  • 3.1536 * 10(9)
  • 3.1536 * 10(16)
  • None of these

16. One year is equal to:
  • 3.2 * 10(7) sec
  • 2.25 * 10(7) sec
  • 3.35 * 10(7) sec
  • All of these

17. Light year is the unit of:
  • Light
  • Time
  • Velocity
  • Distance

18. The unit of thermodynamic temperature is:
  • K
  • C
  • F
  • None of these

19. One atto is:
  • 10(-20)
  • 10(-16)
  • 10(-14)
  • 10(-18)

20. One femto is:
  • 10(-16)
  • 10(-12)
  • 10(-15)
  • 10(-9)

21. The number of significant figure in 8.80 * 10(6) kg is:
  • 1
  • 5
  • 3
  • 6

22. The number 64.350 is rounded off as:
  • 64.35
  • 64.46
  • 64.36
  • 64.4

23. In scientific notation, the number 0.01 may be written as:
  • 10(-2)
  • 10(-4)
  • 10 * 10(-4)
  • 1 * 10(-4)

24. If length = 0.233 m and width = 0.178 m, the most accurate area expressed space of significant figures is:
  • 0.041 m(2)
  • 0.0415 m(2)
  • 0.041747 m(2)
  • None of these

25. The number 0.0001 in scientific notation is:
  • 1 * 10(4)
  • 10(-3)
  • 10 * 10(4)
  • 10(-4)

26. One mega is equal to:
  • 10(6)
  • 10(-6)
  • 10(3)
  • 10(9)

27. The error in a certain measurement occurs due to:
  • Negligence of a person
  • Inappropriate technique
  • Faulty apparatus
  • All of the above

28. The uncertainty may occur due to:
  • Limitation of an instrument
  • Natural variance of the object
  • Personal negligence
  • All of the above

29. The least count of a unit meter rod is:
  • 0.01 cm
  • 0.01 mm
  • Cannot be zero
  • Can be zero

30. The number of base units in SI are:
  • Four
  • Five
  • Six
  • Seven

31. Deca, deci and mega, respectively mean:
  • 10(1), 10(-1), 10(6)
  • 10(6), 10(-1), 10(1)
  • 10(6), 10(1), 10(-1)
  • 10(1), 10(6), 10(-1)

32. 134.7 should be written in scientific notation as:
  • 134.7
  • 13.45 * 10(1)
  • 1.347 * 10(2)
  • 0.1347 * 10(3)

33. Pico, kilo and terra mean:
  • 10(-12), 10(-3), 10(-18)
  • 10(18), 10(3), 10(-12)
  • 10(-12), 10(3), 10(12)
  • 10(18), 10(-12), 10(3)

34. The average time the Earth takes to make exactly one rotation about its axis is defined as:
  • A solar hour
  • A solar day
  • A light year
  • A solar month

35. The distance x determined by the difference between two separate position measurements x1 = 10.5 +-(0.1) cm and x2 26.8 +-(0.1) cm. Then x will be recorded as:
  • 16.3 cm
  • 16.3 +-(0.1) cm
  • 16.3 +-(0.2) cm
  • 16.3 +-(0.01) cm

36. The length of a line was measured with a meter scale of least count = 1 mm by four students. The correct reading will be:
  • 0.5426 m
  • 0.542 m
  • 0.54 m
  • 0.5 m

37. Name the scientist who was awarded the Nobel Prize in physics in 1936 for the discovery of the positron:
  • Chadwick
  • Femi
  • Anderson
  • Einstein

38. The density of mercury is 13600 kg/m(3). Its value in CGS system will be:
  • 13.6 g/cm(3)
  • 1360 g/cm(3)
  • 136 g/cm(3)
  • 1.36 g/cm(3)

39. The unit of force and length are doubled, the unit of energy will be:
  • 1/2 times
  • 1/3 times
  • 2 times
  • 4 times

40. The dimensional formula [ML(0)T(-3)] is more closely associated with:
  • Power
  • Energy
  • Intensity
  • Velocity gradient

41. Which dimensions will be the same as that of time?
  • LC
  • R / L
  • L / R
  • C / L

42. Angular momentum has the same dimensions as:
  • Plank's constant
  • Universal gravitational constant
  • Rydberg constant
  • Boltzmann constant

43. Which of the two have same dimensions?
  • Force and strain
  • Force and stress
  • Angular velocity and frequency
  • Energy and strain

44. A student measured the diameter of a wire using a screw gauge with least count 0.001 cm and listed the measurements. The correct measurement is:
  • 5.320 cm
  • 5.3 cm
  • 5.32 cm
  • 5.3200 cm

45. Zero error belongs to the category of:
  • Constant errors
  • Personal errors
  • Instrumental errors
  • Accidental errors

46. Which one is the least sub-multiple?
  • pico
  • femto
  • atto
  • nano

47. In which system, the unit of force is a base unit:
  • SI system
  • CGS system
  • British engineering system
  • MKS system

48. Which of the following cannot be expressed as Nm(-2):
  • Pressure
  • Stress
  • Surface tension
  • Bulk modulus of elasticity

49. Which of the following units is used to measure the radius of nucleus?
  • Micron
  • Nanometer
  • Angstrom
  • Femtometer

50. Which of the following is not equal to watt?
  • Joule / second
  • Ampere * Volt
  • Ampere(2) * ohm
  • Ampere / volt

51. Temperature can be expressed as a derived quantity in terms of any of the following:
  • Length and mass
  • Mass and time
  • Length, mass and time
  • In terms of none of these

52. erg/m can be the unit of the measure of:
  • Force
  • Momentum
  • Power
  • Acceleration

53. IF the radius of the Earth shrinks by 1.5% (mass remaining same) then the value of acceleration due to gravity changes by:
  • 1%
  • 2%
  • 3%
  • 4%

54. Which of the following readings taken by microscope of least count 0.001 cm is correct?
  • 3.28
  • 3.00
  • 3.000
  • 0.02345

55. Which of the following is not a base unit in SI system:
  • Temperature
  • Amount of substance
  • Light intensity
  • Area

56. The minimum number of physical quantities which define other physical quantities is SI system are:
  • Two
  • Three
  • Five
  • Seven

57. Which of the following is not a unit of time:
  • Leap year
  • Light year
  • Lunar month
  • Micro second

58. Three dimensional angel subtended at the center of the sphere by an area of its surface equal to the square of radius of the sphere is called:
  • Radian
  • Steradian
  • Degree
  • All of the above

59. The ratio of 1 nanometer to 1 attometer is equal to:
  • 1 peta
  • 1 tera
  • 1 giga
  • 1 mega

60. A precise measurement is the one which has:
  • Less absolute uncertainty
  • Less percentage uncertainty
  • Large fractional uncertainty
  • Large absolute uncertainty

61. The accuracy of measurement depends on:
  • Absolute uncertainty
  • Percentage uncertainty
  • Quality of the instrument
  • Calibration of the scale

62. Number of significant figure with increasing degree of approximation:
  • Decreases
  • Increases
  • Remains unchanged
  • None of the above

63. Solid angle subtended at the center by a sphere is:
  • 2 π
  • 4 π
  • 6 π
  • 8 π

64. A second pendulum strikes in a day:
  • 3600 times
  • 86400 times
  • 43200 times
  • 0.003 sec

65. The density of wood is 0.5g/cm(3) in CGS system of units. The corresponding value in SI units is:
  • 500 kg/m(3)
  • 5 kg/m(3)
  • 0.5 kg/m(3)
  • 5000 kg/m(3)

66. Physical quantity is/are:
  • Time
  • Density
  • Temperature
  • All

67. The error is constant for _______ error.
  • Random
  • Systematic
  • Both first and second
  • All

68. For 2450 number of significant digits:
  • 4
  • 3
  • 2
  • 1

69. Which of the following could be measured in the same units as force?
  • Energy / Distance
  • Energy * Distance
  • Energy / Time
  • Momentum * Distance

70. What is the ratio 1 micrometer / 1 Giga meter
  • 10(-3)
  • 10(-6)
  • 10(-12)
  • 10(-15)

Written by: Asad Hussain

Sunday, 19 June 2016

FSc ICS MCAT ECAT Physics Second Year Chapter 18 Electronics Choice Multiple Question (MCQ) Notes

FSc ICS MCAT ECAT Physics Second Year Chapter 18 Electronics Multiple Choice Question (MCQ) Notes

Both Bold and Underlined option is correct

1. The gate, which performs the operation of inversion is called:
  • NOT gate
  • AND gate
  • OR gate
  • XOR gate

2. The gate, which changes the logic level to its opposite level is called:
  • NOR gate
  • AND gate
  • OR gate
  • NOT gate

3. If both the inputs given to a gate are 1, such that the output is 0 then it is:
  • NAND gate
  • NOR gate
  • XOR gate
  • All of these

4. If both the inputs given to a gate are 0 such that the output is 1 then it is:
  • NAND gate
  • NOR gate
  • XNOR gate
  • All of these

5. XNOR gate can be made by combining:
  • OR, NOR, NOT gate
  • OR, AND, NOT gate
  • OR, NAND, NAND gate
  • NOR, AND, NOT gate

6. Breakdown voltage is:
  • 25 V
  • 15 V
  • 35 V
  • 5 V

7. The value of reverse current for Ge is:
  • 1 micro Ampere
  • 1 milli Ampere
  • 1 Ampere
  • 1 Mega Ampere

8. Device used for conversion of D.C. to A.C. is:
  • Oscillator
  • Rectifier
  • Amplifier
  • None

9. p-n junction when reversed biased acts as a:
  • Capacitor
  • On switch
  • Off switch
  • None

10. Pulsating D.C. can be made smooth by using a circuit known as:
  • Filter
  • Tank
  • Accepter
  • All

11. A photodiode can switch its current on Or off in:
  • nano second
  • milli second
  • micro second
  • centi second

12. Photodiode is used in:
  • Automatic switch
  • Optical communication equipment
  • Light meters
  • All

13. Current gain of a transistor which has collector current of 10 mA and a base current of 40 micro Ampere is:
  • 25
  • 250
  • 2500
  • 25000

14. In case of common emitter amplifier, phase difference between input and output:
  • 0 degree
  • 120 degree
  • 180 degree
  • 90 degree

15. When transistor acts as OFF switch then voltage across collector and emitter is _____ Vcc.
  • Less than
  • Greater than
  • Equal to
  • None

16. The photovoltaic cell is always:
  • Forward biased
  • Reverse biased
  • No biasing is required
  • None

17. Under ideal conditions, the collector current is:
  • Equal to base current
  • Nearly equal to emitter current
  • Less than base current
  • Always zero


18. One use of a single p-n junction semiconductor in an electrical circuit is a:
  • Rectifier
  • Transistor
  • Battery
  • Diode

19. The output from a full wave rectifier is:
  • An AC voltage
  • A DC voltage
  • Zero
  • A pulsating unidirectional voltage

20. When n-type semiconductor is heated:
  • Number of electrons increases while holes decreases
  • Number of holes increases while electrons decreases
  • Holes and electrons remains same
  • Holes and electrons increases equally

21. Zener diode is used for:
  • Rectification
  • Amplification
  • Stabilization
  • Modulation

22. In a semi-conducting diode, the reverse biased current is due to drift of free electrons and holes caused by:
  • Thermal excitations only
  • Impurity atoms only
  • Both first and second
  • Neither first nor second

23. In the reverse biased p-n junction, the current is of the order of:
  • Ampere
  • Milliampere
  • Microampere
  • Nanoampere

24. To measure light intensity we use:
  • LED with forward bias
  • LED with reverse bias
  • Photodiode with reverse bias
  • Photodiode with forward bias

25. On increasing the reverse bias to a large value in a p-n junction diode current:
  • Increases slowly
  • Remains fixed
  • Suddenly increases
  • Decreases slowly

26. Rectifier is used to convert:
  • Electrical energy to mechanical energy
  • Heat energy into electrical energy
  • High voltage into low voltage
  • AC into DC

27. In an n-p-n transistor p-type crystal acts as:
  • Emitter only
  • Base only
  • Collector only
  • Either emitter or collector

28. The emitter base junction in the transistor is:
  • Forward biased
  • Reverse biased
  • Either forward or reverse biased
  • Neither forward nor reverse biased

29. The current gain of common-base transistor amplifier is:
  • Less than one
  • More than one
  • Equal to one
  • Zero

30. In common-base transistor amplifier. the phase difference between output voltage and input voltage is:
  • Zero
  • 180 degree
  • 90 degree
  • 45 degree

31. For a common base transistor amplifier the numerical value is least for:
  • Voltage gain
  • Power gain
  • Resistance gain
  • Current gain

32. The base of the transistor is made thin and is doped with least impurity atoms, because:
  • About 95% charge carriers may cross
  • !00% charge carriers may cross
  • the transistor may be saved from high currents
  • None of these

33. A logic gate is an electronic circuit which:
  • Makes logic decisions
  • Allow electron flow only in one direction
  • Allows hole flow only in one direction
  • Alternates between 0 an 1 value


34. Digital circuits can be made by respective use of:
  • AND gates
  • OR gates
  • NOT gates
  • NAND gates

35. Which logic function has the output low only when inputs are high?
  • OR
  • NOR
  • AND
  • NAND

36. In a half wave rectifier the rms value of AC component of the waves:
  • Zero
  • Equal to DC value
  • More than DC value
  • Less than DC value

37. A PN junction has a thickness of the order of:
  • 10(-12) m
  • 10(-6) m
  • 1 mm
  • 1 cm

38. A hole in a p-type semi-conductor is:
  • A donor level
  • An excess electron
  • Missing electron
  • A missing atom

39. If PN junction is forward biased its resistance is:
  • Zero
  • Infinity
  • A few ohm
  • A few kilo ohms

40. A part of transistor which is heavily doped to produce large number of majority carriers is:
  • Emitter
  • Base
  • Collector
  • May be any one

41. How is emitter base junction in the transistor biased?
  • Forward
  • Reverse
  • May be forward or reverse
  • None

42. The potential barrier of silicon diode is:
  • 0.3 V
  • 0.5 V
  • 0.7 V
  • 0.9 V

43. If collector current is 10 mA and base current of 10 microA. What is the current gain of transistor?
  • 250
  • 500
  • 1000
  • None of these

44. An op-amplifier can be used as:
  • Inverting amplifier
  • Night switch
  • Comparator
  • All

45. The output of two input OR gate is zero only when:
  • Both are one
  • Both are zero
  • Either input is 1
  • None

46. The semi-conductor used for fast counting in electronic circuit is:
  • Photodiode
  • LED
  • Photovoltaic cell
  • Solar cell

47. For normal transistor operation Ie is given by:
  • Ie = Ic
  • Ie = Ic + Ib
  • Ie = Ib
  • None

48. The value of open loop gain value for the amplifier is:
  • Zero
  • Infinity
  • Very high
  • Very low

49. The gate will recognized the voltage as 1 if the applied voltage to gate is:
  • 1.5 V
  • 0.5 V
  • 3.5 V
  • 0.7 V

50. In the depletion region of an unbiased PN junction diode there are:
  • Only electrons
  • Only holes
  • Both holes and electrons
  • Ions

51. In a transistor, the conventional current flows from base to emitter. The transistor is:
  • NPN
  • PNP
  • FET
  • None of these

52. In full wave rectifier with input frequency 50 Hz the ripple in the output is mainly of frequency:
  • 25 Hz
  • 50 Hz
  • 100 Hz
  • Zero

53. What is the voltage gain in a common emitter amplifier where input resistance is 3 ohm and load resistance 24 ohm, β = 0.6?
  • 8.4
  • 4.8
  • 2.4
  • 480

54. How many NAND gates are used to form AND gate?
  • 1
  • 2
  • 3
  • 4

55. Photodiode operates when it is:
  • Forward biased
  • Reverse biased
  • Unbiased
  • None

56. The open loop gain of  op-amp is of the order of:
  • 10(3)
  • 10(4)
  • 10(5)
  • 10(6)

57. In  a forward biased p-n junction diode, current inside the junction diode is due to drift of:
  • Free electrons
  • Both types of majority carriers
  • Both types of minority carriers
  • Donor atoms

58. A p-n junction diode cannot be used for:
  • Rectification
  • Amplification
  • Obtaining light radiation
  • Detecting light intensity

59. In a semiconductor diode, p-side is earthed and to n-side is applied a potential of -2 volt; the diode shall:
  • Conduct
  • Not conduct
  • Conduct partially
  • Break down

60. In the symbol for a transistor, the arrow head points in the direction of flow of:
  • Holes 
  • Electrons
  • Majority carriers
  • Minority carriers

61. The current gain of common-emitter transistor amplifier is:
  • Less than one
  • More than one
  • Equal to one
  • Zero

62. In a common-emitter transistor amplifier, the phase difference between output voltage input voltage is:
  • Zero
  • 180 degree
  • 90 degree
  • 45 degree

63. The emitter of a transistor is doped the heaviest because it:
  • Acts as a supplier of charge carriers
  • Dissipates maximum power
  • has a large resistance
  • has a small resistance

64. At room temperature, potential difference develops across the depletion region in case of silicon:
  • 0.3 V
  • 0.7 V
  • 0.8 V
  • 0.9 V

65. Width of depletion region is:
  • 10(-8) m
  • 10(-7) m
  • 10(-6) m
  • 10(-4) m

66. In photovoltaic cell current is _______ proportional to intensity of light.
  • Directly
  • Inversely
  • Both first and second
  • None

67. Silicon transistors are preferred because:
  • High operating temperature
  • Low leakage current
  • Suited to high frequency circuits
  • All

68. If Rc = 10 kΩ , rie = 1kΩ β = 50 then gain of common emitter amplifier:
  • 500
  • 50
  • 5
  • None

69. If R1 = 10 Ωk and R2 = 100kΩ then gain of inverting amplifier is:
  • 10
  • -10
  • 100
  • None

70. Electronic circuits which implement various logic operations are called:
  • Logic gates
  • Boolean algebra
  • Amplifier gain
  • None

Written by: Asad Hussain

Saturday, 18 June 2016

FSc ICS MCAT ECAT Physics Second Year Chapter 17 Physics of Solids Multiple Choice Question (MCQ) Notes

FSc ICS MCAT ECAT Physics Second Year Chapter 17 Physics of Solids Multiple Choice Question (MCQ) Notes

Both Bold and Underlined option is correct

1. Curie temperature is:
  • Different fro chromium oxide and cobalt
  • Same for chromium oxide and cobalt
  • Same for iron and cobalt
  • None of these

2. The steel makes a good permanent magnet and is called:
  • Soft
  • Hard
  • In between
  • None of these

3. Ferromagnetic substances have the small regions are called:
  • Magnets
  • Patches
  • Domains
  • None of these

4. The curie temp for iron is about:
  • 800 degree Celsius
  • 740 degree Celsius
  • 750 degree Celsius
  • 650 degree Celsius

5. The process of introducing a small amount of impurity into the pure semi conductor is called:
  • Overlapping
  • Mixing
  • Doping
  • None of these

6. Which of the following are example of diamagnetic substances?
  • Antimony
  • Cobalt
  • Copper
  • Both first and third

7. Which of the following is not a ferromagnetic substance?
  • Copper
  • Steel
  • Iron
  • Cobalt

8. The permeability of diamagnetic materials:
  • Less than one
  • Greater than one
  • Equal to one
  • Zero

9. The area of hysteresis loop is proportional to the work done in:
  • Magnetizing of the substance
  • Reversing the magnetic field
  • Demagnetizing the substance
  • None of these

10. If a material sets up a magnetic field which opposes the applied magnetic field it is said to be:
  • Electromagnetic
  • Diamagnetic
  • Paramagnetic
  • None of these

11. The domain theory of magnet is important to explain the behaviour of:
  • Diamagnets
  • Paramagnets
  • Ferromagnets
  • All of the above

12. A pentavalent impurity in Si:
  • A free electron and a free hole
  • a free hole
  • a free electron
  • No free particle

13. Unit of Bulk modulus is:
  • No unit
  • N/m(2)
  • N/Pa
  • Pam

14. Formula for strain energy in deformed materials is:
  • EAl1(2)/2L
  • EAl1(2)/2
  • EAl1/3L
  • EAl1/2L(2)

15. At 0 K a piece of silicon is a:
  • Conductor
  • Semi-conductor
  • Insulator
  • All

16. Gallium belongs to _________ group
  • 4 th
  • 2 nd
  • 7 th
  • 3 rd

17. Polythene, polystyrene and nylon etc., are examples of:
  • Crystalline
  • Amorphous
  • Polymers
  • None of these

18. Polymers have ______ specific gravity compared with even the lightest of metals.
  • High
  • Low
  • Zero
  • None of these

19. The strength to weight  ratio of plastic material (chair) is ______ then steel material (chair).
  • Greater
  • Lesser
  • Same
  • All

20. Net charge on n-type material is:
  • Positive
  • Negative
  • Neutral
  • All

21. Energy needed to magnetize and demagnetize is given by:
  • Hysteresis curve
  • Area of loop
  • Coercivity
  • None of these

22. Yttrium bearium copper oxide (YBa2Cu3O7) become superconductor at:
  • 163 K
  • -110 K
  • Both above options
  • None of these

23. Which of the following has the highest elasticity?
  • Rubber
  • Steel
  • Glass
  • All

24. Which of the following has bulk modulus?
  • Water
  • Gas
  • Honey
  • All

25. Out of the following the one which penetrate through 20 cm thick steel plate is:
  • Gamma rays
  • Beat rays
  • Alpha rays
  • Positive rays

26. Crystalline substances mostly exist in:
  • Liquid state
  • Gaseous state
  • Solid state
  • Plasma state

27. Solid have a definite shape on account of:
  • Crystalline structure
  • Small atomic kinetic energy
  • Large atomic kinetic energy
  • Large atomic potential energy

28. Which of the following is not an amorphous structure?
  • Glass
  • Polymers
  • Copper
  • Rubber

29. Conductors, insulators and semiconductors differ from each other due to property of:
  • Ability of the current they carry
  • Formation of crystal lattice
  • Binding energy of their electrons
  • Mutual width of their energy gaps

30. Which of the following is an example of cubic crystal?
  • Calcite
  • Potassium chromate
  • Mercury chloride
  • None of these

31. In an extrinsic semiconductor, the ratio of impurity atoms to that of pure atom is:
  • 1 : 10(8)
  • 10(8) : 1
  • 1 : 10(6)
  • 10(6) : 1

32. The forbidden energy gap in semiconductors:
  • Lies just below the valence band
  • Lies just above the conduction band
  • is the same as the valence band
  • Lies between the valence band and the conduction band

33. In a good conductor, the energy gap between the conduction band and valence band is:
  • Infinity
  • Wide
  • Narrow
  • Zero

34. With rise in temperature the electrical conductivity of intrinsic semiconductor:
  • Increases
  • Decreases
  • First increases and then decreases
  • First decreases and then increases

35. What is the hardest natural substance known?
  • Steel
  • Chromium
  • Tungsten
  • Diamond

36. There is no hole current in good conductors, because they:
  • are full of electron gas
  • have large forbidden gap
  • have no valence band
  • have overlapping valence and conduction bands

37. When a semiconductor is heated its resistance:
  • Decreases
  • Increases
  • Remains the same
  • May increase or decrease depending upon semiconductor

38. The most commonly used semiconductor are:
  • Germanium and silicon
  • Germanium and copper
  • Silicon and glass
  • Glass and ebonite

39. Conductors, semiconductors and insulators are:
  • Work function
  • Width of forbidden energy gap
  • Binding energy of electrons
  • Mobility of electrons

40. In an insulator, the number of electrons in the valence shell, in general, is:
  • Less than 4
  • More than 4
  • Equal to 4
  • None of these

41. The drift velocity of holes as compared to that of electrons is:
  • Less
  • More
  • Equal
  • More or equal

42. The change in the shape of a regular body is due to:
  • Metallic strain
  • Longitudinal strain
  • Bulk strain
  • Shearing strain

43. Energy stored per unit volume in a stretched wire is:
  • (Stress * Strain)/2
  • Stress * Strain
  • Load * Stress
  • (Load * Extension)/2

44. The structure of unit cell is:
  • One dimensional
  • Two dimensional
  • Three dimensional
  • All of these

45. The maximum stress which a body can bear is called:
  • UTS
  • Elastic stress
  • Permanent stress
  • Strain stress

46. In hysteresis when magnetization becomes zero it is:
  • Coercivity
  • Retentivity
  • Saturation
  • Remanance

47. The substance which have partially filled conduction bands are called:
  • Conductors
  • Insulators
  • Semi-conductors
  • Super conductors

48. An example of donor impurity is:
  • Phosphorus
  • Indium
  • Boron
  • Gallium

49. The material whose resistivity becomes zero below a certain temperature:
  • Conductor
  • Semi-conductor
  • Super conductor
  • Insulator

50. Magnetic field produced by spinning nucleus is:
  • Much weaker
  • Much stronger
  • No field
  • All of these

51. Domains contain nearly:
  • 10(8) - 10(10) atoms
  • 10(12) - 10(16) atoms
  • 10(15) - 10(20) atoms
  • None

52. The breaking stress for a wire of unit cross-section is called:
  • Yield point
  • Tensile strength
  • Elastic fatigue
  • Young's modulus

53. Which of the following quantities does not have the unit of force per unit area?
  • Stress
  • Strain
  • Young's modulus
  • Pressure

54. The young's modulus of a perfectly rigid body is:
  • Zero
  • Unit
  • Infinity
  • May have any value

55. The area enclosed by a hysteresis loop is a measure of:
  • Retentivity
  • Suscesptibility
  • Permeability
  • Energy loss

56. The permeability of ferromagneitc substance is:
  • Positive and small
  • Positive and large
  • Negative and small
  • Negative and large

57. Unbalance spin of electron in the atoms is the cause of:
  • Diamagnetism
  • Paramagnetism
  • Ferromagnetism
  • Anti-ferromagnetism

58. A small solid ball of substance is repelled by a pole magnet. The substance may be:
  • Bismuth
  • Aluminium
  • Copper
  • Sodium

59. The type of bonding in Ge crystal is:
  • Ionic
  • Metallic
  • Covalent
  • Van der Waals'

60. If band gap between valence and conduction band material is 5 eV, the material is:
  • An insulator
  • Good conductor
  • Semiconductor
  • Such materials are non-existent

61. In an intrinsic semiconductor:
  • Only electrons are responsible for flow of current
  • Both holes and electrons carry current
  • Both holes and electrons carry current with electrons being majority carriers
  • Only holes are responsible for flow of current

62. Out of following, the intrinsic semiconductor is:
  • Copper
  • Silicon
  • Arsenic
  • Boron

63. The temperature coefficient of resistance of a semiconductor is:
  • Positive always
  • Negative always
  • Zero
  • Infinite

64. The resistivity of intrinsic semiconductor at 0 K is:
  • infinite
  • Zero
  • 1
  • Equal to that at 0 degree Celsius

65. The conductivity of a pure semiconductor can be increased by:
  • Increasing temperature
  • Mixing trivalent impurity
  • Mixing pentavalent impurity
  • All of the above

66. Metals such as copper, iron, zinc are ________ solids.
  • Crystalline
  • Amorphous
  • Polymeric
  • All

67. Conductivity of metals is of the order of:
  • 10(-7) ohm/meter
  • 10 ohm/meter
  • 10(7) per ohm per meter
  • 10(-7) ohm/meter

68. The speed of bullet train can be:
  • 500 km/h
  • 500 km/s
  • 500 m/s
  • 5 km/h

69. Aluminium behaves as super conductor at:
  • 1.18 K
  • 7.8 K
  • 125 K
  • None of these

70. Material which has hysteresis loop of small area is suitable for:
  • Electromagnet
  • Permanent magnet
  • Core of transformer
  • All

Written by: Asad Hussain