When a body is spinning on its axis in the ab | vedclass

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(B) The angular momentum $\vec{L}$ is given by $\vec{L} = I\vec{\omega}$.According to the principle of conservation of angular momentum,if the externa

Vedclass · Accepted Answer

$\vec{L}$ can be changed by keeping $\vec{\omega}$ constant.

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(B) The angular momentum $\vec{L}$ is given by $\vec{L} = I\vec{\omega}$.According to the principle of conservation of angular momentum,if the external torque $\vec{	au} = 0$,then $\frac{d\vec{L}}{dt} = 0$,which implies $\vec{L}$ remains constant.Option $A$ is correct because if the moment of inertia $I$ changes,$\vec{\omega}$ must change to keep $\vec{L}$ constant.Option $B$ is incorrect because if $\vec{L}$ is constant and $\vec{\omega}$ is kept constant,then $I$ must also remain constant. Thus,$\vec{L}$ cannot be changed if $\vec{\omega}$ and $I$ are constant.Option $C$ is correct because $I$ can be changed (e.g.,by changing the distribution of mass),which will result in a change in $\vec{\omega}$ while $\vec{L}$ remains constant.Option $D$ is correct because both $I$ and $\vec{\omega}$ can change simultaneously such that their product $I\vec{\omega}$ remains constant.Therefore,the wrong statement is $B$.

When a body is spinning on its axis in the absence of any external torque,choose the wrong statement.

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