Question

A wooden block of dimensions $40cm\times 20cm\times 10cm$ is found to weigh $5kg$. Find the pressure exerted by the block on a table top, if it is allowed to lie on the top with its sides $20cm\times 10cm$. [Take $g=9.8m{s}^{-2}$]

Answer 1

Step 1: Given data

Mass of wooden block, $m=5kg$

Area, $A=20cm\times 10cm=200c{m}^2=0.02m^2$

Acceleration due to gravity, $g=9.8m{s}^{-2}$

Pressure exerted by the block, $P=?$ (To be calculated)

Step 2: Calculating the force exerted by the block

Force exerted by the wooden block-

$$\begin{gathered} F=m\times g \\ \therefore F=5kg\times 9.8m{s}^{-2}=49N \end{gathered}$$

Step 3: Calculating the pressure exerted by the block

Applying, $Pressure\left(P\right)=\frac{Force\left(F\right)}{Area\left(A\right)}$

$$\begin{gathered} \Rightarrow P=\frac{49N}{0.02m^2} \\ \Rightarrow P=2450Pa \end{gathered}$$

Hence, the pressure exerted by the wooden block is $2450Pa$.