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COMEDK2015PhysicsRotational Motion

A person sitting firmly over a rotating stool has his arms stretched. If he folds his arms, his angular momentum about the axis of the rotation

Options

  1. Aincreases
  2. Bdecreases
  3. Cremains unchanged
  4. Ddoubles

Correct answer

C. remains unchanged

Step-by-step solution

According to conservation of angular momentum, when no external torque is applied on the rotating system, then its angular momentum remains unchanged.

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