A body of moment of inertia about its axis of rotation is `3 kg m^(2)` and angular velocity 3 rad/s. The kinetic energy of rotating body is same as that of body of mass 27 kg moving with a speed of

Options

A. `1.0m//s`
B. `0.5m//s`
C. `1.5m//s`
D. `2.0m//s`

Answer

A

Explanation

`E_(r)=(1)/(2)Iomega^(2)=(1)/(2)xx3xx(3)^(3)=13.5J`
`K.E.=(1)/(2)mv^(2)=(1)/(2)xx27xxv^(2)=13.5impliesv=1m//s`