A circular loop and a disc have the same mass and roll without slipping with the same linear velocity v. If the total K.E. of the loop is 8 J, the K.E. of the disc must be

Options

A. 6J
B. 8J
C. 12J
D. 16J

Answer

1

Explanation

`K_(LOOP)=1/2(2mr^2)omega^2=mV^2=8` (`K=1/2I_pomega^2`where P is contact point which is stationary) `K_(DISK)=1/2(3/2mr^2)omega^2=(3mV^2)/4=6J`.