A circular disc of mass 0.41 kg and radius 10 m rolls without slipping with a velocity of 2 m/s. The total kinetic energy of disc is

Options

A. 0.41 J
B. 1.23 J
C. 0.82 J
D. 2.4 J

Answer

B

Explanation

`KE_("ring")=(1)/(2)mv^(2)[1+K^(2)//R^(2)]`
`=(1)/(2)xx0.41xx4[1+(1)/(2)]`
`=0.41xx2xx(3)/(2)`
`= 1.23 J`.