Question

Q8.A small body attached at the end of an inextensible string completes a vertical circle, then its
(a) angular momentum remains constant
(b) linear momentum remains constant
(c) angular velocity remains constant
(d) total mechanical energy remains constant​

Answer 1

Answer:

Mass of the system is constant and no word is done by any external force (no force is acting in direction of motion only force acting is tension force which is perpendicular to the velocity of the ball so work done is zero) so mechanical energy of the system is conserved .so best possible option is A.

External torquein the form of weight is acting about point O, so angular momentum is not conserved .

External force is acting in form of tension and weight so linear momentum is also not conserved.

As total mechanical energy is conserved and when body goes upwards is gain some potential energy and mechanical energy is decreased hence angular velocity of tge body is changing.

Answer 2

Answer:

total mechanical energy remains constant

Explanation:

chahe to toppar ya doubtnut par dekh le