When a dancer pulls their arms inward while s | vedclass

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(C) According to the law of conservation of angular momentum,if no external torque acts on a system,the angular momentum $L = I\omega$ remains constan

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Conservation of angular momentum and an increase in kinetic energy.

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(C) According to the law of conservation of angular momentum,if no external torque acts on a system,the angular momentum $L = I\omega$ remains constant.When the dancer pulls their arms inward,the moment of inertia $I$ decreases.Since $L = I\omega$ is constant,a decrease in $I$ must lead to an increase in angular velocity $\omega$ to keep $L$ constant.The rotational kinetic energy is given by $K = \frac{L^2}{2I}$.Since $L$ is constant and $I$ decreases,the kinetic energy $K$ increases because the dancer does work by pulling their arms inward against the centrifugal force.

When a dancer pulls their arms inward while spinning on ice,they spin faster. This is due to:

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