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Let \[\overrightarrow A\] be a unit vector along the axis of rotation of a purely rotating body and \[\overrightarrow B\] be a unit vector along the velocity of a particle P of the body away from the axis. The value of \[\overrightarrow A.\overrightarrow B\] is ____________ .

#### Options

1

-1

0

None of these

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#### Solution

0

For a purely rotating body, the axis of rotation is always perpendicular to the velocity of the particle.

Therefore, we have

\[\overrightarrow A.\overrightarrow B=0\]

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