A body of moment of inertia 5 `kgm^(2)` rotating with an angular velocity 6 rad/s has the same kinetic energy as a mass of 20 kg moving with a velocity of ……

Options

A. `5m//s`
B. `4m//s`
C. `3m//s`
D. `2m//s`

Answer

C

Explanation

`KE_("rot")=KE_("line")`
`(1)/(2)I omega^(2) = (1)/(2)m V^(2)`
`therefore " " V^(2)=(I omega^(2))/(m)=(5xx36)/(20)`
`V^(2)=9`
V = 3 m/s.