Question

The pressure exerted by the weight of a cubical block of side 3cm on the surface is 5Pa. Calculate the weight of the block.

Answer 1

Cubical block of side = 3cm = 0.03m

Area of base = 0.03m×0.03m

= 0.0009 m^2

So, we can write as 9×10^-4

Pressure = Force /Area

5 Pa = Force/ 9×10^-4

Force = 45×10^-4

Answer 2

Given :

Length of side of cube = 3 cm = 0.03 m

Pressure (P) = 5 Pa

To Find :

Weight of the block

Solution :

We know, The force acting normally on unit area of a surface is called pressure.

    Pressure = $\frac{Force }{Area}$

Area of the base = (side)² = (0.03)² = 0.0009 m²

∴ Pressure exerted by the weight on the surface = $\frac{Force}{0.0009}$

⇒         5                   =  $\frac{Force}{0.0009}$

⇒      Force               =  0.0045 N

∴ The weight of the block is found to be 0.0045 N