When a rigid body rotates about a fixed axis, all the points in the body have the same A. centripetal acceleration B. tangential acceleration. C. tangential speed. D. angular acceleration E. linear displacement.

The angular acceleration is same at all the points in the body.

Option (D) is correct.

Explanation:

Given:

When a rigid body rotates about a fixed axis, all the points in the body have the same,

For finding which quantity is same we use pure rotational concept,

Where angular frequency, radius of rigid body

When a rigid body rotates about a fixed axis angular velocity of all the points in the body are same.

But the tangential speed, tangential acceleration, linear displacement, and centripetal acceleration depend on the position of the points and hence they are not the same.

Therefore, the angular acceleration is same at all the points in the body.

it should be -8.6 cm hope this out