Question

A solid sphere is in pure rolling motion on an inclined surface having inclination $?$

• A. frictional force acting on sphere is $f=\mu mg cos?$
• B. f is dissipative force
• C. friction will increase its angular velocity and decrease its linear velocity
• D. If $?$ decreases, friction will decrease

Answer 1

Answer: (D)

If $?$ decreases, friction will decrease

Answer 2

In case of pure rolling,
$f=\frac{mg sin ?}{1+\frac{mR^2}{I}}$ (upwards)
$\therefore f?sin ?$
Therefore, as 0 decreases force of friction will also decrease.