Question

A horizontal cylinder is fixed, its inner surface is smooth and its radius is R. A small block is initially at the lowest point. the minimum velocity that should by given to the block at the lowest point, so that it can just cross the point P is u then

(A) If the block moves anti clockwise then u = √(3.5gR)

(B) If the block moves anti clockwise then u = √(3gR)

(C) If the block moves clockwise then u = √(3.5gR)

(D) If the block moves clockwise then u = √(5gR)

Answer 1

Correct option (A) (D)

Explanation:

If the block is moving clockwise, then to cross the point P, the block has to cross the highest point, so to cross the highest point u = √(5gR).