Question

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

Answer 1

Step 1: Given data

First, draw the required diagram,

Given that from the figure,

The coefficient of static friction $\mu =0.2$

The wooden block have mass $m=0.5kg$

The value of $g=10m/s^2$

Step 2: Formula used

Know that the formula,

$f_s={\mu }_{s}N................................\left(1\right)$

And to keep the block adhered to the wall,

$$\begin{gathered} N=F.............................\left(2\right) \\ {f}_s=mg..........................(3 \end{gathered}$$

Step 3: Finding the magnitude of horizontal force.

Now solve from the equation (1),(2), and (3).

$\begin{array}{l}\Rightarrow mg={\mu }_{s}F\\ \Rightarrow F=\frac{mg}{{\mu }_s}\\ \Rightarrow F=\frac{0.5\times 10}{0.2}\\ \Rightarrow F=25N\end{array}$

This happen for all values of $F$greater than or equal to $25N$.

Hence, the magnitude of horizontal force that should be applied on the block to keep it adhere to the wall will be $25N$.