Question

A"V" shaped rigid body has two identical uniform arms. What must be the angle between the two arms so that when the body is hung from one end, the other arm is horizontal ? 

(A) cos^–1 (1/3) 

(B) cos^–1 (1/2) 

(C) cos^–1 (1/4) 

(D) cos^–1 (1/6) 

Answer 1

Correct Option :-  (A) cos^–1 (1/3)

Explanation :-

For one arm to remain horizontal the net torque about O must be zero (in the position shown in the figure) for this OP = OQ