Question

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

Answer 1

0

 

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

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