Question

If block is sliding down on a smooth fixed inclined plane as shown in the figure then net force acting on the wedge due to block is :

• A. $\frac{mg}{\cos \theta }$
• B. $mg$
• C. $mg\cos \theta$
• D. None of these

Answer 1

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

$mg$ is acting downward and its component along an inclined plane is $mgsin\theta$ and the normal component is $mgcos\theta$. Hence the net force acting on the wedge due to the block is equal to the normal reaction $N$, which is equal to $mgcos\theta$.