Statement-$1$: $A$ body is rotating about an axis with angular velocity $\omega$ and moment of inertia $I$. Its angular momentum $L$ remains constant,but its rotational kinetic energy $K$ decreases,provided no external torque is applied.
Statement-$2$: $L = I\omega$ and $K = \frac{L^2}{2I} = \frac{1}{2} I\omega^2$.

  • A
    Statement-$1$ is false,Statement-$2$ is true.
  • B
    Statement-$1$ is true,Statement-$2$ is true,and Statement-$2$ is not the correct explanation of Statement-$1$.
  • C
    Statement-$1$ is true,Statement-$2$ is false.
  • D
    Statement-$1$ is true,Statement-$2$ is true,and Statement-$2$ is the correct explanation of Statement-$1$.

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