Question

A wedge $A$ placed on a rough horizontal surface. Block $B$ of mass $1kg$ slips down the inclined plane (of angle${45}^0$ with horizontal) of the wedge. Find the frictional force acting on wedge $A$ on the rough horizontal surface (in N), if wedge if stationary $(g=10m/s^2).$

Answer 1

$m$ horizontal direction
$f_r=N\sin \theta$
$N=mg\cos \theta$
$f_r=mg\sin \theta \cos \theta$
$=1\times 10\times \frac{1}{\sqrt{2}}\times \frac{1}{\sqrt{2}}=5N$