MCQ
A sphere is rolled on a rough horizontal surface. It gradually shows down and stops. The force of friction tries to:
- AIncrease the angular velocity.
- BDecreases the angular velocity.
- CDecrease the linear velocity.
- ✓Both $A$ and $C$
✓
Answer
Correct option: D.
Both $A$ and $C$
Force of friction produces the torque for rotation.
Therefore, it tries to increase the angular velocity.
However, friction opposes the motion:
Therefore, it tries to decrease the linear velocity.
Therefore, it tries to increase the angular velocity.
However, friction opposes the motion:
Therefore, it tries to decrease the linear velocity.
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