Question

a person standing on rotating table with his hands closed to body now if hands are out stretched then angular movement of person..​

Answer 1

Given:

A person standing on rotating table with his hands closed to body.

To find:

If hands are out stretched then what happens to angular movement of person?

Calculation:

During rotation of a person , since no external torque is involved , the angular momentum remains concerned.

Initially, when the hand is placed close to the body the moment of inertia is less . Now when the hands are stretched out the moment of inertia increases.

Let final moment of Inertia be I2 and initial moment of inertia be I1 :

$\therefore \: L = constant$

$= > \: I \omega= constant$

$= > \:( I 1) (\omega1) =( I2)( \omega2)$

$= > \: \omega2 = \dfrac{( I 1)}{(I2)} (\omega1)$

$= > \: \omega2 < \omega1$

Now , since moment of inertia (I) increases , the angular velocity of the rotating body decreases.

Hence , the angular velocity decreases when hands are stretched out.