9 questions from past BPSC papers, each with the correct answer and an
explanation of why. Free to read — no signup.
How often it has appeared
Paper
67
68
70
71
70Re
Total
Laws of Motion
2
5
1
4
1
13
Questions
63rd Pre · 2018
When a bus suddenly starts moving, passengers fall backward. This is due to:
Inertia of motion
Inertia of rest
Newton's 2nd law
Newton's 3rd law
Why: Body at rest tends to stay at rest — Inertia of REST.
67th Pre · 2022
A bullet of mass 10 g moving at 600 m/s is fired from a 4 kg gun. What is the recoil velocity of the gun?
1.5 m/s
2.5 m/s
3 m/s
4 m/s
Why: Conservation of momentum: 0.01 × 600 = 4 × v ⇒ v = 1.5 m/s.
65th Pre · 2019
Action and reaction forces:
Act on the same body
Act on different bodies
Are unequal
Always cancel each other
Why: Newton's 3rd law — action and reaction act on DIFFERENT bodies.
64th Pre · 2018
SI unit of momentum is:
kg·m/s
N·s
kg·m/s²
Both A and B
Why: kg·m/s = N·s (since 1 N = 1 kg·m/s²).
69th Pre · 2023
Which of the following is NOT a contact force?
Friction
Normal force
Tension
Gravity
Why: Gravity acts at a distance (not contact).
68th Pre · 2023
A goalkeeper pulls his hands backwards after holding the ball. This enables him to
Decrease rate of change of momentum
Exert large force on ball
Increase force exerted by ball on hands
Apply Newton's 1st law
Why: Impulse — extends time of contact.
68th Pre · 2023
Ball bearings are used to convert sliding friction into
Rolling friction
Drag
Static friction
Fluid friction
Why: Sliding → rolling reduces friction.
68th Pre · 2023
A bus takes a sharp right turn suddenly. Passengers will
Bend towards right side
Fall in forward direction
Bend towards left side
Bend backwards
Why: Inertia of direction — body continues straight.
70th Pre · 2024
The meter that is used to measure the distance moved by a vehicle is known as
Ammeter
Speedometer
Chronometer
Odometer
Why: Odometer.
Mains-style questions on this topic
Descriptive questions from past papers. There is no single correct option — practise
writing the answer, then check your structure against the syllabus.
66th Mains GS-1 · 2020
State and explain Newton's three laws of motion with one real-life example each.
Study these topics in order, and remember them
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