SaraNextGen.Com

A child is standing with folded hands at the centre of a platform rotating about its central axis. The kinetic energy of the system is . The child stretches his arms so that the moment of inertia of the system doubles. The kinetic energy of the system now is

a)

b)

c)

d)



Question ID - 100212 | SaraNextGen Top Answer

A child is standing with folded hands at the centre of a platform rotating about its central axis. The kinetic energy of the system is . The child stretches his arms so that the moment of inertia of the system doubles. The kinetic energy of the system now is

a)

b)

c)

d)

1 Answer
127 votes
Answer Key / Explanation : (b) -

(b)

From conservation of angular momentum ( = constant), angular velocity will remain half. As,

The rotational kinetic energy will become half.

127 votes


127