A body of moment of inertia of `3kgm^(2)` rotating with an angular velocity or 2rad//s has the same kinetic energy as a mass of 12kg moving with a velocity of

Options

A. 8m/s
B. 0.5m/s
C. 2m/s
D. 1m/s

Answer

D

Explanation

Rotational kinetic energy of the body `=(1)/(2) I omega^(2)` and translatory kinetic energy `= (1)/(2) mv^(2)`
According to problem `=(1)/(2) I omega^(2)= (1)/(2) mv^(2) rArr (1)/(2) xx 3 xx (2)^(2)= (1)/(2) xx 12 xx v^(2) rArr v= 1m//s`