Question

The coefficient of static friction between a wooden block of mass $0.5\text{kg}$ and a vertical rough wall is $0.2$. The minimum magnitude of horizontal force that should be applied on the block to keep it adhere to the wall will be ______ $\text{N}$.
$[g=10{\text{ms}}^{-2}]$

Answer 1

Given:
${\mu }_s=0.2$
$m=0.5\text{kg}$
$g=10{\text{m/s}}^2$

In equilibrium,
$mg=f$
$\Rightarrow mg={\mu }_{s}N={\mu }_{s}F$
$\Rightarrow F=\frac{mg}{{\mu }_s}=\frac{0.5\times 10}{0.2}=25\text{N}$