A uniform disc of mass m and radius r rotates along an axis passing through its centre of mass and normal to its plane. An unstretchable rope is wound on the disc. Tangential acceleration of a point P on the periphery of the disc when a uniform force F is applied on the rope is

Options

A. `F/(2m)`
B. `(3F)/(2m)`
C. `(F)/(m)`
D. `(2F)/(m)`

Answer

D

Explanation

Using `tau = Fr, tau=Ia,` we get `=Ialpha=1/2 mr^2xxa_t/r` ((where `a_t` is tangential acceleration)
`1/2 m a_(t)=F :. a_t=(2F)/m`