# MCQs on Non-uniform Circular Motion

**MCQs on Non-uniform Circular Motion**

**Q1: A bottle of soap water is grasped by the neck and swings briskly in a vertical circle. Near which portion of the bottle do the bubbles collect**

- Near the bottom
- In the middle of the bottle
- Near the neck
- Uniformly distributed in the bottle

**Answer: (c) Near the neck**

**Q2: A bucket tied at the end of a 1.6 m long spring is whirled in a vertical circle with constant speed. What should be the minimum speed so that the water from the bucket does not spill when the bucket is at the highest position?**

- 4 m/sec
- 6.25 m/sec
- 16 m/sec
- None of the above

**Answer: (a) 4 m/sec**

**Q3: A1 Kg stone at the end of 1 m long string is whirled in a vertical circle at a constant speed of 4 m/sec. The tension in the string is 6 N, when the stone is at **

- Top of the circle
- Bottom of the circle
- Halfway down
- None of the above

**Answer: (a) Top of the circle**

**Q4: A cane filled with water is revolved in a vertical circle of radius 4 metres and the water just does not fall down. The time period of revolution will be**

- 1 sec
- 10 sec
- 8 sec
- 4 sec

**Answer: (d) 4 sec**

**Q5: A 2 Kg stone at the end of a string 1 m long is whirled in a vertical circle at a constant speed. The speed of the stone is 4 m/sec. The tension in the string will be 52N, when the stone is**

- At the top of the circle
- At the bottom of the circle
- Halfway down
- None of these

**Answer: (b )At the bottom of the circle**

**Q6: The string of pendulum of length l is displaced through 90^{0 }from the vertical and released. Then the minimum strength of the string in order to withstand the tension, as the pendulum passes through the mean position is**

- mg
- 3 mg
- 5 mg
- 6 mg

**Answer: (b) 3 mg**

**Q7: In a vertical circle of radius r, at what point in its path does a particle have tension equal to zero, if it is just able to complete the vertical circle**

- Highest point
- Lowest point
- Any point
- At a point horizontally from the centre of the circle of radius r

**Answer: (a) Highest point**

**Q8: A hollow sphere has a radius of 6.4 m. Minimum velocity required by a motorcyclist at the bottom to complete the circle will be**

- 17.7 m/s
- 10.2 m/s
- 12.4 m/s
- 16.0 m/s

**Answer: (a) 17.7 m/s**

**Q9: A fan is making 600 revolutions per minute. If after some time it makes 1200 revolutions per minute, then increase in its angular velocity**

- 10 π rad /sec
- 20 π rad /sec
- 40 π rad /sec
- 60 π rad /sec

**Answer: (b) 20 π rad /sec**

**Q10: A stone tied with a string, is rotated in a vertical circle. The minimum speed with which the string has to be rotated**

- Is independent of the mass of the stone
- Is independent of the length of the stone
- Decreases with increasing mass of the stone
- Decreases with increasing length of the stone

**Answer: (a) Is independent of the mass of the stone**