A body moves on a horizontal circular road of radius `r`, with a tangential acceleration `a_(t)`. The coefficient of friction between the body and the road surface Is `mu`. It begins to slip when its speed is `v`.
(i) `v^(2)=murg`
(ii) `mug=(v^(4)/(r^92))+a_(t))`
(iii) `mu^(2)g^(2)=(v^(4)/(r^(2)+a_(t)^(2))`
(iv) The force of friction makes an angle `tan^(-1)(v^(2)//a_(t)r)` with the direction of motion at the point of slipping.

Options

A. `v^(2)=murg`
B. `mug=(v^(2))/(r)+a_(t)`
C. `mu^(2)g^(2)=(v^(4))/(r^(2))+a_(t)^(2)`
D. The force of friction makes on angle `tan^(-1)(v^(2))//(a_(t)r)` with the direction of motion at the point of slipping .

Answer

c, d