A block of mass `m` is at rest under the action of `F` against the wall as shown in Fig. Which of the following statement is incorrect?

Options

A. f = mg [where f is the friction force]
B. F = N [where N is the normal force]
C. F will not produce torque
D. N will not produce torque

Answer

4

Explanation

The cubical block is in equilibrium For translational equilibrium (a) `sumF_x=0 rArr F=N` (b) `sumF_x=0 rArrf=mg`For Rotational Equilibrium`sumtau_e=0` where `tau_e`=torque about c.m. C Torque created by frictional force (J) about C =f x a in clockwise direction. There should be another torque which should counter this torque. The Normal reaction N on the block acts as shown. This will create a torque `N xx b` in the anticlockwise direction. Such that `f xx `=N x b`.