Practicing these questions will help you:
These questions cover all major areas—Mechanics, Waves, Optics, Heat, Electricity, Magnetism, Modern Physics, and Nuclear Physics—just like real CBT exams.
JAMB Physics is time-based. Constant practice helps you solve questions faster and correctly.
JAMB repeats concepts, not exact questions. Practicing similar questions prepares your brain for the exact pattern of reasoning JAMB uses.
The more you practice, the more familiar you become with CBT-style Physics questions.
Practicing 100 questions helps you discover where you need more study—calculation, theory, electricity, optics, etc.
High Physics scores raise your total aggregate, especially for competitive science courses.
1. The slope of a distance–time graph represents
A. Speed
B. Velocity
C. Acceleration
D. Displacement
Answer: A
2. A car travels 120 km in 3 hours. What is its average speed?
A. 30 km/h
B. 40 km/h
C. 50 km/h
D. 60 km/h
Answer: B
3. A body of mass 5 kg is acted upon by a force of 20 N. What is its acceleration?
A. 2 m/s²
B. 3 m/s²
C. 4 m/s²
D. 5 m/s²
Answer: C
4. A scalar quantity has
A. magnitude only
B. direction only
C. magnitude and direction
D. neither magnitude nor direction
Answer: A
5. Which of the following is NOT a vector?
A. Force
B. Velocity
C. Momentum
D. Speed
Answer: D
6. A projectile has maximum range when the angle of projection is
A. 15°
B. 30°
C. 45°
D. 60°
Answer: C
7. The mass of a body is 10 kg on Earth. What is its mass on the Moon?
A. 10 kg
B. 5 kg
C. 1.6 kg
D. 0 kg
Answer: A
8. The force that opposes motion between two surfaces in contact is
A. Tension
B. Friction
C. Pressure
D. Torque
Answer: B
9. A car moving at 20 m/s comes to rest in 10 seconds. Its deceleration is
A. 1 m/s²
B. 2 m/s²
C. 3 m/s²
D. 4 m/s²
Answer: B
10. The unit of momentum is
A. kg m
B. m/s
C. N
D. kg m/s
Answer: D
11. Work is said to be done when
A. a force acts
B. there is displacement in the direction of force
C. energy increases
D. time is involved
Answer: B
12. Which of the following is a unit of power?
A. Watt
B. Joule
C. Newton
D. Pascal
Answer: A
13. Kinetic energy depends on
A. mass and velocity
B. mass only
C. velocity only
D. acceleration only
Answer: A
14. Potential energy of a raised object increases with
A. temperature
B. mass and height
C. density
D. volume
Answer: B
15. A 50 N force lifts a load through 4 m. The work done is
A. 12 J
B. 100 J
C. 150 J
D. 200 J
Answer: D
16. Efficiency is defined as
A. input/output
B. useful energy / total energy
C. total energy / useful energy
D. work × time
Answer: B
17. The law of conservation of energy states that energy
A. is destroyed
B. is created
C. changes from one form to another
D. is constant in machines
Answer: C
18. Power is
A. work × time
B. work ÷ time
C. force × distance
D. energy × velocity
Answer: B
19. A 2 kg mass moving at 3 m/s has kinetic energy
A. 3 J
B. 6 J
C. 9 J
D. 18 J
Answer: D
20. A 5 kg object is lifted to a height of 2 m. (g = 10 m/s²). Potential energy is
A. 10 J
B. 20 J
C. 50 J
D. 100 J
Answer: D
21. A machine whose MA = 3 means
A. effort is tripled
B. load is tripled
C. energy is tripled
D. velocity triples
Answer: B
22. Pressure is
A. Force per unit area
B. Area per force
C. Force × area
D. Mass per area
Answer: A
23. SI unit of pressure is
A. Joule
B. Watt
C. Pascal
D. Newton
Answer: C
24. Hydraulic press works on
A. Archimedes principle
B. Pascal’s principle
C. Hooke’s law
D. Boyle’s law
Answer: B
25. A lever with the fulcrum between effort and load is a
A. first-class lever
B. second-class lever
C. third-class lever
D. complex lever
Answer: A
26. Atmospheric pressure is measured using
A. manometer
B. hydrometer
C. barometer
D. potentiometer
Answer: C
27. The pressure in a liquid increases with
A. density only
B. height only
C. depth
D. volume
Answer: C
28. Archimedes principle states that the upthrust on a body is equal to
A. mass of body
B. weight of body
C. weight of fluid displaced
D. density of fluid
Answer: C
29. A floating body displaces fluid equal to its
A. weight
B. mass
C. density
D. pressure
Answer: A
30. A block floats because its density is
A. greater than water
B. equal to water
C. less than water
D. independent of water
Answer: C
31. Heat is measured in
A. Joules
B. Celsius
C. Kelvin
D. Watts
Answer: A
32. Temperature is
A. total energy
B. average kinetic energy of molecules
C. potential energy
D. internal pressure
Answer: B
33. Which thermometer is most suitable for measuring high temperature in furnaces?
A. Clinical
B. Mercury-in-glass
C. Thermocouple
D. Alcohol
Answer: C
34. Expansion of solids causes
A. increase in density
B. decrease in density
C. increase in pressure
D. decrease in pressure
Answer: B
35. The fixed points of the Celsius scale are
A. 0°C and 100°C
B. 32°C and 212°C
C. 0 K and 273K
D. 100°C and 200°C
Answer: A
36. Conduction occurs best in
A. gases
B. liquids
C. metals
D. vacuum
Answer: C
37. Radiation requires
A. medium
B. vacuum
C. solid
D. liquid
Answer: B
38. Refrigerator works on
A. conduction
B. convection
C. evaporation
D. radiation
Answer: C
39. Specific heat capacity is
A. heat per unit mass
B. heat per unit temperature rise
C. heat needed to raise 1 kg by 1°C
D. heat × mass
Answer: C
40. Melting is a change from
A. solid to gas
B. gas to liquid
C. liquid to solid
D. solid to liquid
Answer: D
41. Sound cannot travel through
A. liquids
B. vacuum
C. solids
D. gases
Answer: B
42. The pitch of a sound depends on
A. amplitude
B. frequency
C. wavelength
D. speed
Answer: B
43. Echo is heard after
A. 0.01 s
B. 0.1 s
C. 0.5 s
D. 1.0 s
Answer: B
44. Light traveling through a denser medium bends
A. away from normal
B. towards normal
C. without bending
D. sometimes away
Answer: B
45. A converging lens is also called
A. concave lens
B. convex lens
C. diverging lens
D. plain lens
Answer: B
46. The speed of light is approximately
A. 3 × 10⁴ m/s
B. 3 × 10⁵ m/s
C. 3 × 10⁶ m/s
D. 3 × 10⁸ m/s
Answer: D
47. The rainbow is formed due to
A. refraction only
B. dispersion and refraction
C. reflection only
D. diffraction
Answer: B
48. If an object is placed at 2F of a convex lens, image formed is
A. virtual
B. erect
C. the same size
D. inverted
Answer: D
49. The unit of frequency is
A. Hertz
B. Pascal
C. Newton
D. Joule
Answer: A
50. A plane mirror always forms
A. real image
B. inverted image
C. magnified image
D. virtual and erect image
Answer: D
51. The unit of charge is
A. ampere
B. volt
C. coulomb
D. ohm
Answer: C
52. Current is the flow of
A. electrons
B. protons
C. neutrons
D. ions
Answer: A
53. Ohm’s law states that
A. V = IR
B. I = VR
C. R = VI
D. V = P/I
Answer: A
54. The instrument used to measure current is
A. voltmeter
B. galvanometer
C. ammeter
D. potentiometer
Answer: C
55. Resistivity depends on
A. length and area
B. material
C. temperature
D. both B and C
Answer: D
56. 1 kWh is a unit of
A. power
B. energy
C. potential difference
D. heat
Answer: B
57. A diode allows current to pass through in
A. both directions
B. one direction
C. many directions
D. opposite directions
Answer: B
58. A capacitor stores
A. current
B. voltage
C. charge
D. resistance
Answer: C
59. Magnetic field lines travel from
A. north to south
B. south to north
C. east to west
D. west to east
Answer: A
60. Electromagnetic induction was discovered by
A. Einstein
B. Newton
C. Faraday
D. Maxwell
Answer: C
61. The photoelectric effect supports the
A. particle nature of light
B. wave nature
C. sound nature
D. density of light
Answer: A
62. Nuclear fusion occurs in
A. the sun
B. torchlight
C. batteries
D. magnets
Answer: A
63. Radioactivity was discovered by
A. J.J. Thomson
B. Dalton
C. Becquerel
D. Bohr
Answer: C
64. X-rays are produced when
A. electrons collide with metal target
B. protons expand
C. atoms combine
D. heat increases
Answer: A
65. Gamma rays are
A. particles
B. electromagnetic waves
C. liquids
D. ions
Answer: B
66. Electron has a charge of
A. +1.6 × 10⁻¹⁹ C
B. zero
C. –1.6 × 10⁻¹⁹ C
D. –0.5 C
Answer: C
67. An isotope has same
A. mass number
B. atomic number
C. neutrons only
D. electrons only
Answer: B
68. Half-life is the time taken for
A. atoms to double
B. mass to increase
C. half the nuclei to decay
D. electrons to stop
Answer: C
69. The energy of a photon is
A. mc²
B. hv
C. mv²
D. hλ
Answer: B
70. Geiger–Muller tube detects
A. sound
B. light
C. radiation
D. heat
Answer: C
71. If V = 12 V and R = 6 Ω, current is
A. 1 A
B. 2 A
C. 3 A
D. 6 A
Answer: B
72. A transformer has 200 turns on primary and 20 on secondary. The transformer is
A. step-up
B. step-down
C. equal
D. neutral
Answer: B
73. Speed = 15 m/s, time = 20 s. Distance =
A. 150 m
B. 200 m
C. 300 m
D. 400 m
Answer: C
74. A 10 Ω resistor has current 2 A. Voltage is
A. 5 V
B. 10 V
C. 15 V
D. 20 V
Answer: D
75. A force of 15 N acts on 3 kg mass. Acceleration is
A. 2 m/s²
B. 3 m/s²
C. 4 m/s²
D. 5 m/s²
Answer: D
76. The frequency of a wave with speed 300 m/s and wavelength 2 m is
A. 50 Hz
B. 100 Hz
C. 150 Hz
D. 200 Hz
Answer: B
77. Density = mass/volume. A cube of volume 2 m³ and mass 6 kg has density
A. 2 kg/m³
B. 3 kg/m³
C. 4 kg/m³
D. 5 kg/m³
Answer: B
78. Pressure = 1000 N/2 m² =
A. 200 Pa
B. 300 Pa
C. 400 Pa
D. 500 Pa
Answer: D
79. A lens forms image twice the object size; magnification is
A. 0.5
B. 1
C. 2
D. 3
Answer: C
80. If frequency doubles, wavelength
A. doubles
B. halves
C. stays same
D. becomes zero
Answer: B
81. The earth’s gravitational acceleration is approximately
A. 5 m/s²
B. 7 m/s²
C. 9.8 m/s²
D. 12 m/s²
Answer: C
82. Which lens is used to correct long-sightedness?
A. concave
B. convex
C. plane
D. diverging lens
Answer: B
83. A dynamo converts
A. electrical to mechanical
B. mechanical to electrical
C. thermal to electrical
D. electrical to sound
Answer: B
84. Sound travels fastest in
A. vacuum
B. air
C. water
D. metal
Answer: D
85. The charge on a proton is
A. positive
B. negative
C. neutral
D. variable
Answer: A
86. Resistances in series ________
A. add up
B. divide
C. cancel
D. reduce
Answer: A
87. The speed of sound in air is approximately
A. 150 m/s
B. 250 m/s
C. 340 m/s
D. 500 m/s
Answer: C
88. Current is measured in
A. coulomb
B. watt
C. ampere
D. volt
Answer: C
89. A battery is a source of
A. AC
B. DC
C. both AC and DC
D. no current
Answer: B
90. The eye defect where distant objects appear blurry is
A. myopia
B. hypermetropia
C. astigmatism
D. presbyopia
Answer: A
91. A jet of light bends at a boundary due to
A. reflection
B. refraction
C. diffraction
D. interference
Answer: B
92. A compass aligns itself because of
A. electric field
B. solar wind
C. magnetic field of Earth
D. radiation
Answer: C
93. Latent heat is heat
A. causing temperature rise
B. used for change of state
C. lost in vacuum
D. used to increase pressure
Answer: B
94. A fuse is used for
A. heating
B. cooling
C. safety
D. increasing voltage
Answer: C
95. A sound wave is
A. longitudinal
B. transverse
C. electromagnetic
D. nuclear
Answer: A
96. S.I. unit of power is
A. joule
B. watt
C. newton
D. hertz
Answer: B
97. A body moving in a circle experiences
A. centrifugal force
B. centripetal force
C. elastic force
D. friction
Answer: B
98. A transformer works on
A. DC
B. AC
C. battery
D. chemical energy
Answer: B
99. Light year measures
A. time
B. distance
C. brightness
D. speed
Answer: B
100. The speed of a wave is given by
A. f – λ
B. f × λ
C. f ÷ λ
D. λ ÷ f
Answer: B
1. A car accelerates uniformly from rest to 25 m/s in 10 s. What distance is covered?
A. 100 m
B. 120 m
C. 125 m
D. 250 m
Answer: C
(Using: s = ½at², a = 2.5 m/s² → s = 125 m)
2. A projectile is launched at 30 m/s at 60°. What is its maximum height? (g = 10 m/s²)
A. 34.5 m
B. 22.5 m
C. 15.0 m
D. 45.0 m
Answer: A
3. A body moving with speed 15 m/s comes to rest with deceleration of 3 m/s². Time taken is
A. 3 s
B. 4 s
C. 5 s
D. 6 s
Answer: C
4. The moment of a force is maximum when the angle is
A. 0°
B. 45°
C. 60°
D. 90°
Answer: D
5. The centre of mass of a uniform rod lies at
A. one end
B. mid-point
C. one-quarter
D. three-quarter
Answer: B
6. A bullet of mass 0.02 kg traveling at 200 m/s is stopped by a wall in 0.01 s. Force exerted is
A. 200 N
B. 300 N
C. 400 N
D. 500 N
Answer: D
7. Terminal velocity occurs when
A. air resistance becomes zero
B. weight = upthrust
C. weight = drag
D. acceleration is maximum
Answer: C
8. A 2-kg block is pulled with 10 N on a rough table. If friction is 4 N, acceleration is
A. 2 m/s²
B. 3 m/s²
C. 4 m/s²
D. 5 m/s²
Answer: A
9. Impulse is equal to
A. change in force
B. rate of momentum
C. change in momentum
D. force per time
Answer: C
10. A body moving in a circle at constant speed has
A. no acceleration
B. tangential acceleration
C. centripetal acceleration
D. linear acceleration only
Answer: C
11. A machine has efficiency 40% and does 200 J useful work. Input work is
A. 400 J
B. 450 J
C. 500 J
D. 600 J
Answer: C
12. An object of 5 kg moves at 20 m/s. Its kinetic energy is
A. 500 J
B. 1000 J
C. 1500 J
D. 2000 J
Answer: B
13. A pump lifts 4000 kg of water to height 20 m in 10 s. Power is (g=10)
A. 80 kW
B. 60 kW
C. 40 kW
D. 20 kW
Answer: C
14. A spring constant is 200 N/m. If stretched by 0.1 m, energy stored is
A. 0.5 J
B. 1.0 J
C. 2.0 J
D. 4.0 J
Answer: A
15. Efficiency of an ideal machine is
A. 0%
B. 50%
C. 90%
D. 100%
Answer: D
16. A cube of 10 cm side has mass 2 kg. Density is
A. 2000 kg/m³
B. 3000 kg/m³
C. 4000 kg/m³
D. 5000 kg/m³
Answer: C
17. A 5 m column of oil (density 800 kg/m³). Pressure at base =
A. 12 kPa
B. 20 kPa
C. 30 kPa
D. 40 kPa
Answer: B
18. Hydrometer measures
A. density
B. pressure
C. weight
D. volume
Answer: A
19. If upthrust equals weight, object will
A. sink
B. float
C. rise
D. oscillate
Answer: B
20. Boyle’s law holds at
A. constant temperature
B. constant pressure
C. constant volume
D. constant density
Answer: A
21. Heat capacity of 2 kg copper (c = 400 J/kgK)
A. 200 J/K
B. 400 J/K
C. 600 J/K
D. 800 J/K
Answer: D
22. A substance changes state at constant temperature because
A. molecules stop moving
B. latent heat is absorbed
C. pressure is constant
D. volume reduces
Answer: B
23. Thermal expansion of liquids is measured using
A. vernier caliper
B. micrometer
C. thermometer
D. hydrometer
Answer: C
24. Radiation is best in
A. shiny surface
B. painted surface
C. black surface
D. white surface
Answer: C
25. If 2000 J of heat raises temperature by 5°C, heat capacity is
A. 200 J/K
B. 400 J/K
C. 500 J/K
D. 1000 J/K
Answer: B
26. If wave travels 300 m in 0.5 s, speed is
A. 100 m/s
B. 300 m/s
C. 400 m/s
D. 600 m/s
Answer: D
27. Two waves interfere destructively when phase difference is
A. 0°
B. 90°
C. 120°
D. 180°
Answer: D
28. A sound has frequency 800 Hz and velocity 320 m/s. Wavelength is
A. 0.2 m
B. 0.3 m
C. 0.4 m
D. 0.5 m
Answer: C
29. Critical angle occurs when light moves from
A. air to glass
B. glass to air
C. vacuum to water
D. water to glass
Answer: B
30. A concave lens always forms
A. real, inverted
B. real, erect
C. virtual, erect
D. magnified
Answer: C
31. The speed of sound in water is approximately
A. 340 m/s
B. 500 m/s
C. 1200 m/s
D. 1500 m/s
Answer: D
32. A lens produces an image with magnification –3. Image is
A. erect
B. inverted
C. virtual
D. smaller
Answer: B
33. Diffraction is more pronounced when
A. wavelength ≈ slit size
B. slit is large
C. amplitude is high
D. frequency is high
Answer: A
34. In a prism, deviation is minimum when
A. angle of incidence is zero
B. angle of refraction is zero
C. angle of incidence = angle of emergence
D. angle between rays is 90°
Answer: C
35. Power of lens is measured in
A. joules
B. diopters
C. pascals
D. hertz
Answer: B
36. A 6 Ω resistor draws 2 A. Power =
A. 12 W
B. 24 W
C. 36 W
D. 48 W
Answer: B
37. Electric field intensity is
A. force per charge
B. voltage per charge
C. charge per force
D. work per time
Answer: A
38. The total resistance of 3Ω, 6Ω, 9Ω in series is
A. 18Ω
B. 20Ω
C. 15Ω
D. 25Ω
Answer: A
39. The same resistors in parallel give
A. 1.0 Ω
B. 2.0 Ω
C. 3.0 Ω
D. 4.5 Ω
Answer: B
40. A 240 V heater draws 10 A. Time to use 2 kWh?
A. 0.5 h
B. 1 h
C. 2 h
D. 3 h
Answer: C
41. A 5C charge passes in 0.2 s. Current =
A. 10 A
B. 20 A
C. 25 A
D. 30 A
Answer: B
42. Potential difference is
A. work done per charge
B. charge per force
C. power × time
D. energy × charge
Answer: A
43. Induced EMF is proportional to
A. magnetic field strength
B. rate of change of flux
C. coil resistance
D. coil length
Answer: B
44. A magnet freely suspended aligns
A. north–south
B. east–west
C. vertically
D. randomly
Answer: A
45. Transformer ratio for Vp= 240 V, Vs = 12 V is
A. 5
B. 10
C. 15
D. 20
Answer: D
46. Energy of a photon =
A. hv
B. h/λ
C. mc²
D. mv²
Answer: A
47. Electron volt is a unit of
A. momentum
B. power
C. energy
D. frequency
Answer: C
48. Half-life of substance is 20 min. After 60 min, remaining mass is
A. 1/2
B. 1/3
C. 1/4
D. 1/8
Answer: D
49. Nuclear fission is
A. splitting heavy nuclei
B. combining light nuclei
C. breaking molecules
D. radiation of particles
Answer: A
50. Cathode rays are
A. protons
B. neutrons
C. electrons
D. photons
Answer: C
51. X-rays are produced by
A. accelerating electrons
B. slowing electrons suddenly
C. heating metals
D. cooling metals
Answer: B
52. A nuclide has atomic number 20, mass number 43. Neutrons =
A. 20
B. 21
C. 22
D. 23
Answer: C
53. Pair production requires a photon of energy
A. 0.32 MeV
B. 0.51 MeV
C. 1.02 MeV
D. 2.04 MeV
Answer: C
54. Beta decay increases
A. mass number
B. atomic number
C. neutron number
D. proton+neutron ratio
Answer: B
55. A Geiger counter is used to measure
A. energy
B. current
C. radiation
D. force
Answer: C
56. A 10 µF capacitor charged to 200 V stores energy
A. 0.1 J
B. 0.2 J
C. 0.3 J
D. 0.5 J
Answer: B
57. If 40 J of work moves charge 5 C, potential difference is
A. 4 V
B. 5 V
C. 8 V
D. 10 V
Answer: C
58. A copper wire of resistance 10 Ω is heated, increasing resistance by 20%. New R =
A. 10 Ω
B. 11 Ω
C. 12 Ω
D. 13 Ω
Answer: C
59. Force on a 2 C charge in electric field 4 N/C
A. 2 N
B. 4 N
C. 6 N
D. 8 N
Answer: D
60. 100 turns coil linking flux 0.05 Wb. EMF = 500 V. Time =
A. 0.01 s
B. 0.02 s
C. 0.05 s
D. 0.1 s
Answer: A
61. A gas at 400 K is cooled to 200 K at constant pressure. Its volume becomes
A. doubled
B. halved
C. same
D. quadrupled
Answer: B
62. A force of 50 N acts on lever arm 0.2 m. Torque =
A. 5 Nm
B. 10 Nm
C. 15 Nm
D. 25 Nm
Answer: A
63. The escape velocity from Earth is approximately
A. 1 km/s
B. 5 km/s
C. 8 km/s
D. 11 km/s
Answer: D
64. A body moving with 10 m/s has momentum 50 kg·m/s. Mass =
A. 2 kg
B. 5 kg
C. 10 kg
D. 50 kg
Answer: B
65. Efficiency = power output ÷ power input. If input = 500 W, output = 300 W
A. 30%
B. 50%
C. 60%
D. 80%
Answer: C
66. A convex lens forms an image at 30 cm when object is 15 cm away. Magnification =
A. 0.5
B. 1
C. 2
D. 3
Answer: C
67. If refractive index of water is 1.33, critical angle is
A. 42°
B. 48°
C. 50°
D. 53°
Answer: A
68. Light of frequency 6×10¹⁴ Hz and speed 3×10⁸ m/s has wavelength
A. 400 nm
B. 500 nm
C. 600 nm
D. 700 nm
Answer: A
69. A concave mirror with focal length 10 cm forms real image when object distance is
A. < 10 cm
B. exactly 10 cm
C. > 10 cm
D. infinite
Answer: C
70. Dispersion occurs because
A. different colors travel at different speeds
B. reflection occurs
C. refraction is constant
D. absorption occurs
Answer: A
71. If coil length doubles but area halves, inductance
A. doubles
B. halves
C. becomes 1/4
D. becomes 1/2
Answer: C
72. Resistivity increases with
A. pressure
B. temperature in metals
C. volume
D. area
Answer: B
73. Electrons flow from
A. high to low potential
B. low to high
C. positive to negative
D. nucleus to electrons
Answer: A
74. Two capacitors of 6 µF each in series give
A. 3 µF
B. 6 µF
C. 12 µF
D. 18 µF
Answer: A
75. If an AC supply has peak voltage 100 V, RMS voltage is
A. 50 V
B. 60 V
C. 70.7 V
D. 100 V
Answer: C
76. Rest mass of photon is
A. zero
B. infinite
C. 1 × 10⁻³¹
D. 9 × 10⁻³¹
Answer: A
77. Neutrons are used in nuclear reactors because
A. they are fast
B. they are slow and neutral
C. they carry current
D. they produce heat
Answer: B
78. A radioactive sample decays from 80 g to 10 g in 3 hours. Half-life is
A. 30 minutes
B. 1 hour
C. 1.5 hours
D. 2 hours
Answer: B
79. Fusion releases more energy than fission because
A. electrons are involved
B. lighter nuclei combine
C. proton charge is higher
D. neutron mass is conserved
Answer: B
80. X-ray hardness depends on
A. temperature
B. accelerating voltage
C. atomic mass
D. current
Answer: B
81. A wave has frequency 400 Hz and wavelength 0.5 m. Speed =
A. 100 m/s
B. 150 m/s
C. 200 m/s
D. 250 m/s
Answer: C
82. The magnetic field in a solenoid is increased by
A. fewer turns
B. air core
C. increasing current
D. reducing current
Answer: C
83. Internal resistance causes
A. increase in voltage
B. drop in terminal voltage
C. increase in current
D. increase in power
Answer: B
84. Which radiation has highest ionizing power?
A. alpha
B. beta
C. gamma
D. X-rays
Answer: A
85. Loudness depends on
A. frequency
B. amplitude
C. speed
D. quality
Answer: B
86. If force on conductor = BIL, and direction is reversed, force becomes
A. zero
B. half
C. doubled
D. negative
Answer: D
87. The area under velocity-time graph gives
A. acceleration
B. displacement
C. momentum
D. distance × time
Answer: B
88. A 60 W bulb runs for 2 hours. Energy used is
A. 120 J
B. 7200 J
C. 72000 J
D. 432000 J
Answer: D
89. A body weighed 100 N in air and 60 N in water. Upthrust =
A. 20 N
B. 40 N
C. 60 N
D. 80 N
Answer: B
90. A transformer steps 240 V to 24 V. If output current is 10 A, input current is
A. 1 A
B. 2 A
C. 5 A
D. 10 A
Answer: A
91. The speed of light in glass (n = 1.5)
A. 1.0×10⁸
B. 1.5×10⁸
C. 2.0×10⁸
D. 3.0×10⁸
Answer: C
92. A 1 F capacitor and 1 Ω resistor connected in series have time constant
A. 0.1 s
B. 0.5 s
C. 1 s
D. 2 s
Answer: C
93. Kelvin scale starts at
A. –273°C
B. 0°C
C. 273°C
D. 100°C
Answer: A
94. The force constant of two springs in parallel is
A. sum
B. difference
C. product
D. reciprocal
Answer: A
95. If wave amplitude doubles, energy becomes
A. same
B. doubled
C. quadrupled
D. halved
Answer: C
96. A nuclear reaction releases 3×10⁻¹⁰ J. Mass converted is
A. 1×10⁻²⁷ kg
B. 3×10⁻²⁷ kg
C. 3×10⁻²⁶ kg
D. 9×10⁻²⁷ kg
Answer: A
97. A force acts on charge moving perpendicular to magnetic field. Work done is
A. maximum
B. zero
C. doubled
D. half
Answer: B
98. Photoelectric emission depends on
A. frequency
B. amplitude
C. intensity only
D. pressure
Answer: A
99. Fuse wire melts because of
A. high resistance
B. low resistance
C. high voltage
D. low current
Answer: A
100. For total internal reflection: θ >
A. 45°
B. 57°
C. critical angle
D. angle of incidence
Answer: C
