FSc Part 1 Physics chapter 5: Circular motion MCQs with answers

By Team Megalecture · Updated 4 Nov 2026

27 exam-style questions on Circular motion, each with the answer and a short explanation. Ten of them are below to try. The chapter test draws ten fresh questions each time and is marked the moment you finish, with your score by topic.

27 questions · 3 topics · 10 per test

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What chapter 5 covers

Ten Circular motion questions with answers

Try each one, then open the answer. These ten stay the same; the test draws new ones every time.

1. A space station of radius 40 m rotates to give artificial gravity equal to g at its rim. Its frequency of rotation must be about

  1. A
    0.079 Hz
  2. B
    0.49 Hz
  3. C
    0.25 Hz
  4. D
    12.7 Hz
Show answer

Answer: A. g = ω2R, so ω = √(9.8/40) = 0.495 rad s−1 and f = ω/2π = 0.079 Hz. 0.49 is ω, not f; 12.7 is the period in seconds.

2. For a disc rolling without slipping, what fraction of its total kinetic energy is rotational?

  1. A
    1/2
  2. B
    1/3
  3. C
    2/3
  4. D
    1/4
Show answer

Answer: B. Translational K.E. = ½mv2; rotational K.E. = ½(½mr2)ω2 = ¼mv2. Rotational fraction = ¼ ÷ ¾ = 1/3. (For a hoop it would be 1/2.)

3. A 0.50 kg ball moves at 4.0 m s−1 in a circle of radius 2.0 m. The centripetal force on it is

  1. A
    1 N
  2. B
    2 N
  3. C
    4 N
  4. D
    8 N
Show answer

Answer: C. F = mv2/r = 0.50 × 16/2.0 = 4 N. Using v instead of v2 gives 1 N.

4. A stone is whirled in a horizontal circle on a string, and the string suddenly breaks. The stone then moves

  1. A
    along the tangent to the circle at that point
  2. B
    radially outwards
  3. C
    towards the centre
  4. D
    on the same circle
Show answer

Answer: A. With no centripetal force the stone keeps the velocity it had, which is along the tangent. There is no outward force pushing it radially.

5. A hoop and a disc have the same mass and radius. About the axis through the centre perpendicular to the plane,

  1. A
    the disc has the greater moment of inertia
  2. B
    both have the same moment of inertia
  3. C
    the hoop has the greater moment of inertia
  4. D
    it depends on how fast they rotate
Show answer

Answer: C. Hoop: I = mr2; disc: I = ½mr2. All the hoop's mass is at the rim, far from the axis.

6. A bucket of water is swung in a vertical circle of radius 1.0 m. What is the least speed at the top for the water not to fall out?

  1. A
    9.8 m s−1
  2. B
    4.43 m s−1
  3. C
    1.0 m s−1
  4. D
    3.13 m s−1
Show answer

Answer: D. At the minimum speed, gravity alone supplies the centripetal force: mg = mv2/r, so v = √(gr) = √9.8 = 3.13 m s−1.

7. A skater spinning at 2.0 rad s−1 has moment of inertia 4.0 kg m2. She pulls in her arms, reducing it to 1.6 kg m2. Her new angular velocity is

  1. A
    0.8 rad s−1
  2. B
    3.2 rad s−1
  3. C
    5.0 rad s−1
  4. D
    8.0 rad s−1
Show answer

Answer: C. I1ω1 = I2ω2: 4.0 × 2.0 = 1.6 × ω2, so ω2 = 5.0 rad s−1.

8. A 70 kg man stands on a weighing machine in a lift. The lift cable breaks and the lift falls freely. The machine now reads

  1. A
    686 N
  2. B
    zero
  3. C
    1372 N
  4. D
    70 N
Show answer

Answer: B. In free fall a = g, so R = m(g − a) = 0. The man is still attracted by the Earth (686 N), but his apparent weight is zero.

9. A wheel turns at 300 revolutions per minute. Its angular velocity is

  1. A
    5 rad s−1
  2. B
    31.4 rad s−1
  3. C
    300 rad s−1
  4. D
    1885 rad s−1
Show answer

Answer: B. 300 rev min−1 = 5 rev s−1, and ω = 2π × 5 = 31.4 rad s−1. 1885 forgets to divide by 60; 5 forgets the 2π.

10. A satellite orbits at speed v in a circular orbit. If it were in an orbit of four times the radius, its speed would be

  1. A
    v/4
  2. B
    v/2
  3. C
    2v
  4. D
    v
Show answer

Answer: B. v = √(GM/r), so v ∝ 1/√r. Four times the radius gives 1/√4 = ½ the speed.

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Ways to practise this chapter

Circular motion: questions students ask

How many Circular motion MCQs are there?

27, each with the answer and a short explanation, across 3 topics: Angular motion and centripetal force, Moment of inertia, angular momentum and rotational kinetic energy, Artificial satellites and weightlessness. Every chapter test draws ten of them, so you can take it many times.

Is the FSc Part 1 Physics chapter 5 test free?

Yes. The test, the answers and the explanations are free and need no sign-up. Sign in only if you want your scores kept across devices.

How is the chapter test marked?

The moment you press Finish: your score, the right answer and an explanation for every question, and the ones you got wrong saved in My mistakes to retry.

Can I read the explanations in Urdu?

Yes. In practice mode and on your results you can switch the explanations to Urdu.

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