Question

A cubical block of 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 fiction is sufficiently high so that the block does not slide before toppling , the minimum force required o topple the block is

• A. infinitesimal
• B. mg/4
• C. mg/2
• D. mg(1-$\mu$)

Answer 1

The correct option is C mg/2

For minimum force for toppling the normal should pass through point A

Balancing torque about point A, for minimum F:

$FL\ge mg\times \frac{L}{2}$

so the minimum force is $\frac{mg}{2}$