A small coin of mass 40 g is placed on the horizontal surface of a rotating disc. The disc starts from rest and is given a constant angular acceleration `alpha="2 rad s"^(-2)`. The coefficient of static friction between the coin and the disc is `mu_(s)=3//4` and the coefficient of kinetic friction is `mu_(k)=0.5.` The coin is placed at a distance `r=1m` from the centre of the disc. The magnitude of hte resultant force on the coin exerted by the disc just before it starts slipping on the disc is :

Options

A. 0.2 N
B. 0.3 N
C. 0.4 N
D. 0.5 N

Answer

D