AP EAMCET202018 Sep 2020Morning ShiftPhysicsRotational MotionActual

A ballet dancer suddenly folds her outstretched arms. Her angular velocity

Options

Aincreases
Bdecreases
Cremains the same
Dmay increase or decrease

Correct answer

A. increases

Step-by-step solution

According to law of conservation of angular momentum, (I = constant )...(i) where, (I= ) moment of inertia and ( = ) angular velocity. When a ballet dancer suddenly folds her outstretched arms, then her moment of inertia decreases, hence from Eq. (i), we observe that her angular velocity will increases.

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