✅ RRB Physics MCQs (CBSE Class 10 Level) – Chapter Wise Practice Set (100 Questions)
SECTION A: Electricity (1–25)
1. The SI unit of potential difference is:
A) Ampere B) Volt C) Ohm D) Watt
2. The unit of electric charge is:
A) Coulomb B) Ampere C) Volt D) Joule
3. The resistance of a conductor increases when:
A) Length decreases
B) Area increases
C) Length increases
D) Temperature decreases
4. Ohm’s law states that:
A) V ∝ 1/I
B) V ∝ I (at constant temperature)
C) I ∝ R
D) R ∝ V
5. A fuse is connected in:
A) Parallel B) Series C) Both D) None
6. 1 kWh equals:
A) 1000 J
B) 3.6 × 10⁶ J
C) 3.6 × 10⁵ J
D) 36 × 10⁶ J
7. Electric power is given by:
A) P = VI
B) P = IR
C) P = V/R
D) P = I/R
8. The instrument used to measure potential difference is:
A) Ammeter B) Voltmeter C) Galvanometer D) Thermometer
9. Current in a circuit is measured in:
A) Volt B) Watt C) Ampere D) Ohm
10. A wire of length L is doubled. Its resistance becomes:
A) R/2 B) R C) 2R D) 4R
11. For a given material, resistance depends on:
A) Length and area
B) Area only
C) Length only
D) None
12. When resistors are connected in parallel, total resistance:
A) Increases
B) Decreases
C) Becomes infinite
D) Becomes zero
13. The heating effect of electric current is used in:
A) Electric heater
B) Electric iron
C) Electric bulb
D) All of these
14. The filament of bulb is made of:
A) Copper B) Aluminium C) Tungsten D) Iron
15. If current is doubled in a conductor, heat produced becomes:
A) Half
B) Double
C) Four times
D) One-fourth
16. The device used to control current in a circuit is:
A) Fuse
B) Rheostat
C) Switch
D) Voltmeter
17. Resistance of a wire increases if:
A) Diameter increases
B) Length decreases
C) Diameter decreases
D) Material changes to good conductor
18. Current is the rate of flow of:
A) Energy B) Charge C) Power D) Heat
19. Electric energy consumed is measured by:
A) Voltmeter
B) Ammeter
C) Energy meter
D) Galvanometer
20. Resistance of an ideal ammeter is:
A) 0 B) Very high C) Infinite D) 1 Ω
21. Resistance of an ideal voltmeter is:
A) 0 B) Very low C) Very high D) 1 Ω
22. The correct relation is:
A) V = IR
B) I = VR
C) R = VI
D) P = IR
23. Copper is used for wires because it has:
A) High resistance
B) Low resistance
C) High melting point only
D) No conductivity
24. In series circuit, current is:
A) Different in each resistor
B) Same in all resistors
C) Zero
D) Infinite
25. The unit of electrical power:
A) Joule B) Watt C) Coulomb D) Ampere
SECTION B: Light – Reflection & Refraction (26–50)
26. The focal length of convex lens is:
A) Negative B) Positive C) Zero D) Infinite
27. A lens which can form real image:
A) Concave lens
B) Convex lens
C) Plane mirror
D) Prism
28. The image formed by plane mirror is:
A) Real, inverted
B) Virtual, erect
C) Real, erect
D) Virtual, inverted
29. Rear-view mirrors in vehicles are:
A) Concave mirror B) Convex mirror C) Plane mirror D) Lens
30. Power of a lens is measured in:
A) Watt B) Dioptre C) Ohm D) Newton
31. Myopia is corrected using:
A) Convex lens B) Concave lens C) Cylindrical lens D) Prism
32. Hypermetropia is corrected using:
A) Concave lens B) Convex lens C) Prism D) Mirror
33. The phenomenon of bending of light in medium is:
A) Reflection B) Refraction C) Scattering D) Dispersion
34. Refractive index of vacuum is:
A) 1 B) 0 C) 1.33 D) 2
35. Speed of light is maximum in:
A) Glass B) Water C) Air D) Vacuum
36. The power of a lens is negative for:
A) Convex lens B) Concave lens C) Plane lens D) None
37. The focal length of concave lens is:
A) Positive B) Negative C) Zero D) Infinite
38. A concave lens forms image which is:
A) Real & inverted
B) Virtual & erect
C) Real & erect
D) None
39. The splitting of white light is called:
A) Reflection B) Refraction C) Dispersion D) Scattering
40. Mirages are due to:
A) Dispersion
B) Total internal reflection
C) Diffraction
D) Reflection
41. The unit of focal length:
A) Watt B) cm or m C) Dioptre D) Ohm
42. A convex mirror always forms:
A) Real image
B) Virtual & diminished image
C) Virtual & magnified image
D) Real & magnified
43. The phenomenon responsible for blue sky:
A) Refraction
B) Dispersion
C) Scattering
D) Reflection
44. The mirror used by dentist:
A) Plane mirror B) Concave mirror C) Convex mirror D) None
45. A real image can be obtained on:
A) Mirror only
B) Screen
C) Retina only
D) Lens only
46. In reflection from plane mirror, angle of incidence equals:
A) 0°
B) 45°
C) Angle of reflection
D) 90°
47. Magnifying glass uses:
A) Concave lens
B) Convex lens
C) Concave mirror
D) Plane mirror
48. The image formed by concave mirror when object is between pole and focus:
A) Real, inverted
B) Virtual, erect, magnified
C) Virtual, diminished
D) Real, erect
49. Refractive index is ratio of:
A) v/vacuum
B) speed in vacuum / speed in medium
C) speed in medium / speed in vacuum
D) wavelength only
50. Rainbow formation is due to:
A) Reflection only
B) Refraction only
C) Dispersion + internal reflection
D) Scattering only
SECTION C: Magnetic Effects of Current (51–75)
51. Magnetic field around a straight conductor forms:
A) Straight lines
B) Circular lines
C) Parallel lines
D) No field
52. Right-hand thumb rule gives direction of:
A) Current only
B) Voltage
C) Magnetic field
D) Resistance
53. Device that converts electrical energy into mechanical energy:
A) Generator B) Motor C) Transformer D) Battery
54. Fleming’s left-hand rule is for:
A) Generator B) Motor C) Heater D) Fuse
55. Fleming’s right-hand rule is for:
A) Motor B) Generator C) Fan D) Battery
56. Electromagnetic induction refers to:
A) Heating effect
B) Current due to changing magnetic field
C) Static electricity
D) Reflection of waves
57. Strongest magnetic field in a solenoid is:
A) Outside coil
B) Inside coil
C) At far distance
D) Nowhere
58. The SI unit of magnetic field is:
A) Ampere
B) Tesla
C) Volt
D) Coulomb
59. A current carrying coil behaves like:
A) Resistor
B) Magnet
C) Battery
D) Lens
60. The core used in electromagnet is:
A) Aluminium
B) Iron
C) Copper
D) Lead
61. To increase strength of electromagnet:
A) Decrease current
B) Increase turns and current
C) Remove coil
D) Use plastic core
62. Magnetic field lines inside magnet are:
A) North to south
B) South to north
C) Random
D) Zero
63. Current induced in coil depends on:
A) Change in magnetic field
B) Number of turns
C) Speed of motion
D) All of these
64. AC means:
A) Always current
B) Alternating current
C) Accurate current
D) Active current
65. DC means:
A) Double current
B) Direct current
C) Driving current
D) Dynamic current
66. Transformer works on:
A) Heating effect
B) Electromagnetic induction
C) Reflection
D) Gravitation
67. The frequency of AC in India is:
A) 60 Hz B) 50 Hz C) 100 Hz D) 25 Hz
68. The component used to produce magnetic field in motor is:
A) Armature
B) Field magnet
C) Both
D) None
69. The induced current is maximum when:
A) Coil is stationary
B) Magnetic field changes fastest
C) No magnet
D) No turns
70. Magnetic field at centre of circular loop is maximum if:
A) Current decreases
B) Current increases
C) Loop radius increases
D) Turns decrease
71. Which is NOT a magnetic material?
A) Iron B) Nickel C) Cobalt D) Copper
72. The direction of current induced is given by:
A) Right-hand thumb rule
B) Fleming’s right-hand rule
C) Fleming’s left-hand rule
D) Newton’s law
73. The strength of magnetic field around wire increases if:
A) Current decreases
B) Current increases
C) Wire length increases
D) Resistance increases
74. Electric motor is based on:
A) Heating effect
B) Force on current carrying conductor in magnetic field
C) Refraction
D) Dispersion
75. A generator converts:
A) Electrical to heat
B) Electrical to chemical
C) Mechanical to electrical
D) Electrical to mechanical
SECTION D: Motion, Force & Gravitation (76–100)
76. SI unit of force:
A) Joule B) Watt C) Newton D) Pascal
77. Acceleration is:
A) Change in velocity/time
B) Change in distance/time
C) speed × time
D) force × time
78. Newton’s 2nd law relates force with:
A) Mass only
B) Acceleration only
C) Mass and acceleration
D) Velocity only
79. Weight of object depends on:
A) Mass only
B) Gravity only
C) Mass and gravity
D) Temperature
80. SI unit of work is:
A) Joule B) Newton C) Watt D) Pascal
81. Power is:
A) Work × time
B) Work / time
C) Force / time
D) Work / force
82. The value of g on earth ≈
A) 98 m/s²
B) 9.8 m/s²
C) 0.98 m/s²
D) 1.8 m/s²
83. Friction acts in direction:
A) Same as motion
B) Opposite to motion
C) Perpendicular
D) None
84. Momentum =
A) m + v
B) m × v
C) m / v
D) v / m
85. Unit of momentum:
A) kg m/s
B) N m
C) J/s
D) kg m²/s²
86. The rate of change of momentum is:
A) Power
B) Force
C) Energy
D) Work
87. Universal law of gravitation says:
A) Force ∝ m1m2 / r²
B) Force ∝ r²
C) Force ∝ 1/r
D) Force ∝ m1+m2
88. Pressure =
A) Force × area
B) Force / area
C) Area / force
D) Work / time
89. SI unit of pressure:
A) Newton
B) Pascal
C) Joule
D) Watt
90. Archimedes’ principle is related to:
A) Force
B) Buoyancy
C) Gravity
D) Motion
91. If displacement is zero, work done is:
A) Maximum
B) Minimum
C) Zero
D) Infinite
92. Force needed to stop an object depends on:
A) Only speed
B) Only mass
C) Both mass and speed
D) Temperature
93. 1 horsepower =
A) 746 W
B) 1000 W
C) 100 W
D) 10 W
94. The value of acceleration due to gravity decreases when:
A) Going above earth surface
B) Going below earth
C) Both
D) None
95. Sound cannot travel in:
A) Air
B) Water
C) Vacuum
D) Steel
96. A body in free fall has acceleration:
A) 0
B) g
C) 2g
D) ½ g
97. The motion of earth around sun is due to:
A) Friction
B) Gravitational force
C) Magnetic force
D) Electrostatic force
98. The centre of gravity of a uniform rod is:
A) One end
B) Middle point
C) 1/4th length
D) Random
99. Kinetic energy depends on:
A) mass only
B) velocity only
C) mass and velocity
D) temperature
100. Formula for kinetic energy is:
A) mgh
B) ½ mv²
C) Fs
D) ma
✅ Answer Key (1–100)
1-B, 2-A, 3-C, 4-B, 5-B, 6-B, 7-A, 8-B, 9-C, 10-C,
11-A, 12-B, 13-D, 14-C, 15-C, 16-B, 17-C, 18-B, 19-C, 20-A,
21-C, 22-A, 23-B, 24-B, 25-B,
26-B, 27-B, 28-B, 29-B, 30-B,
31-B, 32-B, 33-B, 34-A, 35-D,
36-B, 37-B, 38-B, 39-C, 40-B,
41-B, 42-B, 43-C, 44-B, 45-B,
46-C, 47-B, 48-B, 49-B, 50-C,
51-B, 52-C, 53-B, 54-B, 55-B,
56-B, 57-B, 58-B, 59-B, 60-B,
61-B, 62-B, 63-D, 64-B, 65-B,
66-B, 67-B, 68-C, 69-B, 70-B,
71-D, 72-B, 73-B, 74-B, 75-C,
76-C, 77-A, 78-C, 79-C, 80-A,
81-B, 82-B, 83-B, 84-B, 85-A,
86-B, 87-A, 88-B, 89-B, 90-B,
91-C, 92-C, 93-A, 94-C, 95-C,
96-B, 97-B, 98-B, 99-C, 100-B
✅ RRB Physics MCQs (CBSE Class 10) – Explanations for Answer Key (1–100)
SECTION A: Electricity (1–25) Explanations
1. (B) Volt – Potential difference is measured in volts.
2. (A) Coulomb – Charge is measured in Coulombs (C).
3. (C) Length increases – Resistance ∝ length, so resistance increases with length.
4. (B) V ∝ I – Ohm’s law: V = IR at constant temperature.
5. (B) Series – Fuse must be in series to break the circuit when current is high.
6. (B) 3.6×10⁶ J – 1 kWh = 1000 W × 3600 s = 3.6×10⁶ J.
7. (A) P = VI – Electric power = Voltage × Current.
8. (B) Voltmeter – Voltmeter measures potential difference.
9. (C) Ampere – Current unit is ampere (A).
10. (C) 2R – Resistance ∝ length → doubled length gives double resistance.
11. (A) Length and area – R = ρL/A, depends on length and area.
12. (B) Decreases – In parallel, effective resistance decreases.
13. (D) All – Heater, iron, bulb all use heating effect of current.
14. (C) Tungsten – High melting point, used in bulb filament.
15. (C) Four times – Heat ∝ I²Rt. Doubling current increases heat 4 times.
16. (B) Rheostat – Rheostat changes resistance and controls current.
17. (C) Diameter decreases – Smaller area increases resistance (R ∝ 1/A).
18. (B) Charge – Current is rate of flow of charge.
19. (C) Energy meter – Measures electrical energy consumption in kWh.
20. (A) 0 – Ammeter must have very low resistance (ideal = 0).
21. (C) Very high – Voltmeter must have very high resistance.
22. (D) All – Actually correct formula: V=IR; But from given options, the only correct one is A (if asked). In our key: 22-D was incorrect. ✅ Correct answer should be: 22-A (V=IR).
23. (D) – In our key 23-D is wrong. Copper is used because it has low resistivity / high conductivity. ✅ Correct answer: 23-B (low resistance).
24. (B) Same – In series, same current flows through each component.
25. (B) Watt – Electrical power is measured in watts.
📌 Note: Two answers in Electricity section need correction:
✅ Q22 = A (not D)
✅ Q23 = B (not D)
SECTION B: Light (26–50) Explanations
26. (B) Positive – Convex lens has positive focal length.
27. (B) Convex lens – Convex lens can form real image on screen.
28. (B) Virtual, erect – Plane mirror forms virtual, erect image.
29. (B) Convex mirror – Provides wider field of view, used in vehicles.
30. (B) Dioptre – Power P = 1/f(m), unit dioptre (D).
31. (B) Concave lens – Myopia (near-sightedness) corrected by concave lens.
32. (B) Convex lens – Hypermetropia corrected by convex lens.
33. (B) Refraction – Bending of light in medium is refraction.
34. (A) 1 – Refractive index of vacuum is 1.
35. (D) Vacuum – Speed of light is highest in vacuum.
36. (B) – Concave lens has negative focal length hence negative power.
37. (B) Negative – Concave lens has negative focal length.
38. (B) – Concave lens always forms virtual and erect image.
39. (C) Dispersion – Splitting white light into colours.
40. (B) Total internal reflection – Mirage due to total internal reflection.
41. (B) – Focal length is measured in metre or cm.
42. (B) – Convex mirror forms virtual, erect, diminished image always.
43. (C) Scattering – Sky appears blue due to scattering (Rayleigh).
44. (B) Concave mirror – Dentist mirror forms magnified image.
45. (B) Screen – Real image can be formed on screen.
46. (C) – Angle of incidence = angle of reflection.
47. (B) Convex lens – Magnifying glass uses convex lens.
48. (B) – Object between pole & focus gives virtual, erect, magnified image.
49. (B) – n = speed in vacuum / speed in medium.
50. (C) – Rainbow due to dispersion + total internal reflection + refraction.
SECTION C: Magnetism (51–75) Explanations
51. (B) – Magnetic field lines around straight wire are concentric circles.
52. (C) – Right-hand thumb rule gives magnetic field direction.
53. (B) Motor – Motor converts electrical energy to mechanical energy.
54. (B) – Fleming’s left-hand rule for motors.
55. (B) – Fleming’s right-hand rule for generators.
56. (B) – Changing magnetic field induces current = electromagnetic induction.
57. (B) – Inside solenoid magnetic field is strong and uniform.
58. (B) Tesla – SI unit of magnetic field is Tesla (T).
59. (B) – Current carrying coil behaves like a magnet.
60. (B) Iron – Soft iron core increases magnetic strength.
61. (B) – More turns + more current → stronger electromagnet.
62. (B) – Inside magnet field lines go South to North.
63. (D) – Induced current depends on turns, speed, change in field.
64. (B) – AC = Alternating Current.
65. (B) – DC = Direct Current.
66. (B) – Transformer works on electromagnetic induction.
67. (B) – AC frequency in India = 50 Hz.
68. (C) – Both field magnet and armature are important parts of motor.
69. (B) – Faster change in magnetic field → greater induced current.
70. (B) – Magnetic field increases when current increases.
71. (D) Copper – Copper is non-magnetic.
72. (B) – Fleming’s right hand rule gives direction of induced current.
73. (B) – Magnetic field ∝ current, so increases when current increases.
74. (B) – Motor principle: force on conductor in magnetic field.
75. (C) – Generator converts mechanical energy into electrical energy.
SECTION D: Motion/Force/Gravitation (76–100) Explanations
76. (C) Newton – SI unit of force is Newton.
77. (A) – Acceleration = change in velocity / time.
78. (C) – F = m × a (Newton’s second law).
79. (C) – Weight W = mg, depends on mass and gravity.
80. (A) Joule – SI unit of work is Joule.
81. (B) – Power = work / time.
82. (B) – g ≈ 9.8 m/s² on Earth.
83. (B) – Friction opposes the motion.
84. (B) – Momentum = mass × velocity (p = mv).
85. (A) – Unit kg m/s.
86. (B) – Force = rate of change of momentum.
87. (A) – Gravitational force ∝ m1m2 / r².
88. (B) – Pressure = Force / Area.
89. (B) Pascal – SI unit of pressure.
90. (B) – Archimedes principle relates to buoyancy (upward force).
91. (C) – Work = Force × displacement → if displacement = 0, work = 0.
92. (C) – Stopping force depends on mass and speed (momentum).
93. (A) – 1 HP = 746 watts.
94. (C) – g decreases above and below Earth’s surface.
95. (C) – Sound needs medium; cannot travel in vacuum.
96. (B) – In free fall acceleration = g.
97. (B) – Earth revolves due to gravitational force.
98. (B) – Uniform rod centre of gravity at middle.
99. (C) – KE depends on mass and velocity.
100. (B) – KE = ½mv².
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