Question

Area of cross section of a brick is (30 cm x 20 cm). It weighs 24 N . Pressure exerted by the brick on the ground will be: *

Answer 1

Answer

Pressure exerted by the brick on the ground will be 400 Pa

Given

Area of cross section of a brick is (30 cm x 20 cm). It weighs 24 N

To Find

Pressure exerted by the brick on the ground will be

Have a look at

Pressure is defined as force acting per unit area

$\to\ \rm Pressure=\dfrac{Force}{Area}$

→ SI unit of Pressure is Pascal

→ SI unit of Force is Newton

→ SI unit of Area is m/s²

Solution

Area of cross section , A = 30 × 20 cm²

⇒ A = 600 cm²

⇒ A = 600 (10⁻² m)²

⇒ A = 600 × 10⁻⁴ m²

⇒ A = 6 × 10⁻² m²

Weight , F = 24 N

Pressure , P = ? N/m²

Apply formula ,

$\rm \to\ Pressure=\dfrac{Force}{Area}\\\\\rm \to\ P=\dfrac{F}{A}\\\\\to\ \rm P=\dfrac{24}{6\times 10^{-2}}\\\\\to\ \rm P=4\times 10^2\\\\\to\ \rm P=4\times 100\\\\\to\ \rm P=400\ N/m^2\\\\\to\ \rm P=400\ Pa$

So , Pressure exerted by the brick on the ground will be 400 Pa