The second #39;s hand of a watch has len

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The second's hand of a watch has length $6\,\, cm$. Speed of end point and magnitude of difference of velocities at two perpendicular positions will be

A

$6.28$ and $0 \,\,mm/s$

B

$8.88$ and $4.44 \,\,mm/s$

C

$8.88$ and $6.28 \,\,mm/s$

D

$6.28 $ and $8.88 \,\,mm/s$

The second's hand of a watch has length $6\,\, cm$. Speed of end point and magnitude of difference of velocities at two perpendicular positions will be

$v = r\omega = \frac{{r \times 2\pi }}{T} = \frac{{0.06 \times 2\pi }}{{60}} = 6.28\,mm/s$

Magnitude of change in velocity = $|\overrightarrow {{v_2}} - \overrightarrow {{v_1}} |$

$ = \sqrt {v_1^2 + v_2^2} = 8.88\,mm/s$ $\left( {{\rm{As\,}}{v_1} = {v_2} = 6.28\,mm/s} \right)$