Question

A block is kept on an inclined plane of angle ${30}^o$. The coefficient of kinetic friction between block and the inclined plane is $1\sqrt{3}$.What is the acceleration of the block ?

• A. Zero
• B. $2m/s^2$
• C. $1.5m/s^2$
• D. $5m/s^2$

Answer 1

The correct option is A Zero

Acceleration of block $a=g\sin \theta -\mu g\cos \theta$

$a=10\times \sin {30}^o-\frac{1}{\sqrt{3}}\times 10\cos {30}^o$

Or $a=10\times \frac{1}{2}-\frac{1}{\sqrt{3}}\times 10\times \frac{\sqrt{3}}{2}$

$⟹a=0$