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(C) For a body in pure rotation,the axis of rotation is the line about which all particles of the body move in circular paths.The velocity vector $\ve

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(C) For a body in pure rotation,the axis of rotation is the line about which all particles of the body move in circular paths.The velocity vector $\vec{v}$ of any particle $P$ in a rotating body is always tangent to its circular path.Since the circular path lies in a plane perpendicular to the axis of rotation,the velocity vector $\vec{v}$ (and thus the unit vector $\vec{B}$) is always perpendicular to the axis of rotation (and thus the unit vector $\vec{A}$).Therefore,the angle $	heta$ between $\vec{A}$ and $\vec{B}$ is $90^{\circ}$.The dot product is given by $\vec{A} \cdot \vec{B} = |\vec{A}| |\vec{B}| \cos 	heta$.Since $|\vec{A}| = 1$,$|\vec{B}| = 1$,and $\cos 90^{\circ} = 0$,we get $\vec{A} \cdot \vec{B} = 1 	imes 1 	imes 0 = 0$.

Let $\vec{A}$ be a unit vector along the axis of rotation of a purely rotating body and $\vec{B}$ be a unit vector along the velocity of a particle $P$ of the body away from the axis. The value of $\vec{A} \cdot \vec{B}$ is

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