A kathak dancer is standing on a horizontal s | vedclass

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(B) The rotational kinetic energy $K$ of a rotating body is given by the formula $K = \frac{1}{2} I \omega^2$, where $I$ is the moment of inertia and

Vedclass · Accepted Answer

$K/3$

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(B) The rotational kinetic energy $K$ of a rotating body is given by the formula $K = \frac{1}{2} I \omega^2$, where $I$ is the moment of inertia and $\omega$ is the angular velocity.Initially, $K = \frac{1}{2} I \omega^2$.After the dancer stretches his arms, the new moment of inertia $I' = 3I$ and the new angular velocity $\omega' = \frac{1}{3} \omega$.The new kinetic energy $K'$ is given by:$K' = \frac{1}{2} I' (\omega')^2$$K' = \frac{1}{2} (3I) (\frac{1}{3} \omega)^2$$K' = \frac{1}{2} (3I) (\frac{1}{9} \omega^2)$$K' = \frac{1}{3} (\frac{1}{2} I \omega^2)$Since $K = \frac{1}{2} I \omega^2$, we have $K' = \frac{K}{3}$.

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