Question

A sphere can roll on a surface inclined at an angle $\theta$ if the friction coefficient is more than $\frac{2}{7}g\sin \theta$. Suppose the friction coefficient is $\frac{1}{7}g\sin \theta$. If a sphere is released from rest on the inclined,

• A. it will stay at rest.
• B. it will make pure translational motion.
• C. it will translate and rotate about the centre.
• D. the angular momentum of the sphere about its centre will remain constant.

Answer 1

Answer: (C)

it will translate and rotate about the centre.

As there is not enough friction for rolling the sphere will both translate and rotate about the center.