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## Homework Statement

**A Person sitting firmly over a rotating stool has his arms stretched. If he fold his arms, his angular momentum about the axis of rotation :**

A.) Increases

B.) Decreases

C.) Remains Unchanged

D.) doubles

A.) Increases

B.) Decreases

C.) Remains Unchanged

D.) doubles

## Homework Equations

[/B]Conservation of Angular Momentum

## The Attempt at a Solution

**Since External Torque =0**

Then final angular momentum = initial angular momentum

=> (C.)

Then final angular momentum = initial angular momentum

=> (C.)

But I wanted to further ask that in the Equation L=I*(omega)

since L has to be constant(if external torque = 0) then:

If I increases then omega decreases to keep L constant

or if omega increases then I decreases to keep constant

__Will folding his arms increase I( Moment of Inertia ) or decrease it??__