Question

A body of mass m slides down an incline and reaches the bottom with a velocity v. If the same mass was in the form of a ring which rolls down this incline, the velocity of the ring at the bottom would have been –

• A. v
• B. $\sqrt{2}$v
• C. v/$\sqrt{2}$
• D. ($\sqrt{2/5}$) v

Answer 1

Answer: (C)

v/$\sqrt{2}$

Answer 2

When body slides, v = $\sqrt{2gh}$ ....(1)

When ring rolls, v' = $\sqrt{\frac{2gh}{1 + k^{2}/r^{2}}}$= $\sqrt{\frac{2gh}{2}}$=$\frac{v}{\sqrt{2}}$