Direction of centripetal force is always:
- Tangential
- Perpendicular
- Radially inward
- Outward
Show answer and explanation
Answer: C. Radially inward
Centripetal force always points radially inward, towards the centre of the circular path.
FSC Physics: Circular Motion, questions with answers
Practise 25 real Federal Board questions on Circular Motion from 2023 to 2026. See the answer and explanation as soon as you answer.
25real questions
10multiple choice
5exam sessions
About Circular Motion in FSC Physics
Circular Motion is one of the 14 main chapters in our Federal Board FSC Physics question bank (11th class), and about 5% of its real questions come from it. Tayyari Karo has 25 real questions on this chapter from 2023 to 2026; 10 are multiple choice and marked instantly, and the rest are short and long questions with a model answer. By difficulty: 18 medium, 7 easy.
Work through the questions below, then open the explanation for each one. Redo the ones you missed a few days later.
Try 8 real questions
These are real past-paper questions. Think of your answer first, then open the explanation.
If distance from axis increases, moment of inertia:
- Decreases
- Increases
- Remains constant
- Becomes zero
Show answer and explanation
Answer: B. Increases
Moment of inertia I = mr², so it increases as the distance r from the axis increases.
Magnitude of centripetal force F_c =
- mrω²
- mrω
- mω²
- mv²
Show answer and explanation
Answer: A. mrω²
F_c = mv²/r = mrω² (using v = rω).
The SI unit of angular velocity is:
- Rad
- N·m
- m/s²
- rad/s
Show answer and explanation
Answer: D. rad/s
Angular velocity = angle/time, so its SI unit is radian per second (rad/s).
The centripetal force for a body of mass m moving with speed v in a circle of radius r is:
- mv
- mv²r
- mv²/r
- m/r²
Show answer and explanation
Answer: C. mv²/r
Centripetal force Fc = mv²/r, directed towards the centre of the circle.
Minute hand of a clock is 2 m long. What will be its angular speed?
- 1.256×10² rad s⁻¹
- 6.28 rad s⁻¹
- 1.7×10⁻³ rad s⁻¹
- 1.04×10⁻¹ rad s⁻¹
Show answer and explanation
Answer: C. 1.7×10⁻³ rad s⁻¹
The minute hand completes one revolution (2π rad) in 3600 s: ω = 2π/3600 ≈ 1.7×10⁻³ rad s⁻¹.
The front wheel of a tractor travels 700 revolutions while the rear wheel travels 280 revolutions in a time interval of 40 seconds. Find their angular velocities.
Show model answer
Angular velocity ω = (angle in radians)/time = (2πN)/t
Front wheel: ω_front = (2π×700)/40 = 1400π/40 = 35π
ω_front ≈ 110.0 rad/s
Rear wheel: ω_rear = (2π×280)/40 = 560π/40 = 14π
ω_rear ≈ 44.0 rad/s
What is meant by angular momentum? Determine the angular momentum of a rigid body.
Show model answer
Angular momentum (L) of a particle about a point is the moment of its linear momentum, defined as L̄ = r̄ × p̄ = r̄ × mv̄, a vector quantity with SI unit kg·m²/s.
Angular momentum of a rigid body: Consider a rigid body rotating about a fixed axis with angular velocity ω. It consists of many particles; a particle of mass mᵢ at perpendicular distance rᵢ from the axis moves with speed vᵢ = rᵢω, and its angular momentum about the axis is:
Lᵢ = mᵢvᵢrᵢ = mᵢ(rᵢω)rᵢ = mᵢrᵢ²ω
Total angular momentum of the rigid body = sum over all particles:
L = Σ mᵢrᵢ²ω = ω Σ mᵢrᵢ²
Since moment of inertia I = Σ mᵢrᵢ²:
L = Iω …
The full model answer is in the app.
Sessions with Circular Motion questions
| Session | Questions |
|---|---|
| 2026 Annual | 5 |
| 2025 1st Annual | 6 |
| 2025 2nd Annual | 4 |
| 2024 Annual | 5 |
| 2023 Annual | 5 |
Common questions
What does the Circular Motion chapter cover on this page?
25 real Federal Board (FBISE) Physics questions on Circular Motion from 2023 to 2026, for 11th class. Each one shows the session it came from.
Are the answers official?
No. We could not find an official FBISE marking scheme for these papers, so the answers and explanations are written by Tayyari Karo for practice. Check anything important with your teacher or textbook.
Is it free?
You can start free with no signup. A small set of papers per subject is free, and Premium unlocks the full question bank.