Question

A small cart with a sphere suspended from ceiling by a string is moving up an inclined plane at a speed V. The direction of string supporting the sphere is 

(A) Vertical 

(B) Horizontal 

(C) Perpendicular to the inclined plane 

(D) None of these

Answer 1

Correct option is (A) Vertical

Let us assume that the string makes an angle of ‘θ₁ ’ with the normal of the plane.

The only external force acting on the sphere is ‘mg’ which is vertically downward. Hence the string also becomes vertical so as to balance the force mg.

Answer 2

Correct answer is (A) Vertical