Question

A sphere is released on a smooth inclined plane from the top. When it moves down its angular momentum is:

• A. conserved about every point
• B. conserved about the point of contact only
• C. conserved about the centre of the sphere only
• D. conserved about any point on a fixed line parallel to the inclined plane and passing through the centre of the ball.

Answer 1

The correct option is A conserved about every point

As the inclined plane is smooth, the sphere can never roll, rather it will just slip down. Hence, the angular momentum remains conserved about any point on a line parallel to the inclined plane and passes through the center of the ball.