Question

A block of mass m is stationary on a rough inclined plane making an angle $\theta$ with the horizontal Find the force between block and the plane

• A. $mg$
• B. $mgsin\theta$
• C. $mgcos\theta$
• D. $mgtan\theta$

Answer 1

The correct option is A $mg$

Solution

REF.Image

Consider the FBD as :

At Equilibrium

$N=mgcos\theta$

$f=mgsin\theta$

Force between block and plane =

$\sqrt{N^2+f^2}=\sqrt{m^2{g}^{2}co{s}^2\theta +m^2{g}^{2}si{n}^2\theta }$

$=mg$

Option - A is correct.