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A ball of mass m is attached to a string...

A ball of mass `m` is attached to a string whose other end is fixed. The system is free to rotate in vertical plane. When the ball swings, no work is done on the ball by the tension in the string. Which of the following statement is the correct explanation?

A

Tension is always perpendicular to the direction of motion of the ball.

B

Tension is an internal force for the ball.

C

Tension is an external force for the ball.

D

Since the ball is swinging about the axis, total displacement is zero.

Text Solution

Verified by Experts

The correct Answer is:
A
Tension acts rediially inward and velocity is tangetial so tension is always `bot` to the direction of motion of ball.
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