Question

A block of mass $10Kg$ is placed on a rough inclined wedge, at an angle of ${37}^{\circ }$.The coefficient of static friction ${\mu }_s=0.5$. Two forces of magnitude $60N$ and $75N$ acting on the block is shown in the figure. Find the acceleration of the block if the block is initially at rest.

Answer 1

$m=10kg;\mu =0.5;\theta ={37}^0$
$N=10gcos{37}^{\circ }=80N$
Now $0\le f_s\le \mu N$
$0\le f_s\le 0.5\times 80$
$\therefore f_s\le 40N$
We will put value off in the last i.e. in the direction opposite to resultant of other forces. f acts down the incline and its value is of $=75-60=$15 N
So acceleration is zero