question_answer

A Cubical block of mass m and side L rests on a rough horizontal surface with coefficient of friction\[\mu .\] A horizontal force F is applied on the block as shown. If the coefficient of friction is sufficiently high, so that block does not slide before toppling,  the minimum force to topple the block is :

A)  mg/2                           

B)  mg/4

C)  \[mg(1-\mu )\]               

D)  \[mg(1+\mu )\]

Correct Answer: A

Solution :

maximum torque due to F should be greater then torque due to mg about the axis of rotation, lower edge.             Torque = force \[F\times L=mg\times L/2\]