Question

A block of mass 8 kg is at rest on a rough inclined plane as shown in the figure below. The magnitude of net force exerted by the surface on the block will be (g=10 m/s)

• A. 40N
• B. $40\sqrt{3}N$
• C. 60N
• D. 80N

Answer 1

The correct option is B $40\sqrt{3}N$

We know that force exerted on a inclined an will be

$\begin{array}{c}F=mg\cos \theta \\ F=8\times 10\times \cos {30}^0\\ F=80\times \frac{\sqrt{3}}{2}\\ F=40\times \sqrt{3}N\end{array}$

Hence,

option $\left(B\right)$ is correct answer.