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)
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)
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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 |
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a) |
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b) |
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c) |
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d) |
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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
Answer Link
127