Question

A person sitting firmly over a rotating stool has his arms stretched. If he folds his arms, his angular momentum about the axis of rotation
(a) increases
(b) decreases
(c) remains unchanged
(d) doubles.

Answer 1

Answer:

C.

Explanation:

THIS ANGULAR VELOCITY WILL BE INCREASED AND M.I WILL BE DECREASED SO L= ANGULAR MOMENTUM REMAINS UNCHANGED

Answer 2

A person sitting firmly over a rotating stool has his arms stretched. If he folds his arms, his angular momentum about the axis of rotation remains unchanged

Explanation:

A person who sits securely on a spinning stool has spread his arms.When he folds his back, his angular momentum around the rotation axis will "remain unchanged"

There is no external torque, according to the question.

Now, we know that the angular momentum is preserved if there is no external torque.

Therefore the correct answer is Option (c)remains unchanged