Question

A block of mass $m$ is placed on a smooth inclined plane of inclination $\theta$ with the horizontal. The force exerted by the plane on the block has magnitude:

• A. $mg\tan \theta$
• B. $mg\cos \theta$
• C. $mg/cos\theta$
• D. $mg$

Answer 1

The correct option is B $mg\cos \theta$

Here the force excreted by the plane on the block is the normal force $N$ of the block. so from FBD, $N=mgcos\theta$