Question

A block of mass $2$ kg rests on a rough inclined plane making an angle of ${30}^0$ with the horizontal. The coefficient of static friction between the block and the plane is $\mathrm{0.7.}$ The frictional force on the block is

• A. $9.8N$
• B. $0.7\times 9.8\times \left(\sqrt{3}\right)$ N
• C. $9.8\times \left(\sqrt{3}\right)$N
• D. $0.7\times 9.8$ N

Answer 1

The correct option is A $9.8N$

Given that,

Mass of the block, $m=2$ kg

Angle of inclination between the block and the horizontal line is given as :

$\theta ={30}^0$

Also,

Coefficient of friction, $\mu =0.65$

The force that tends to slide the body on the inclined plane can be given by,

$f=mgsin\theta$

$\left[A\right]F=2\times 9.8\times 0.5=9.8N$