A 2 cm cubical block of mass 2 kg is lying on the ground. What is the pressure exerted by the block on the ground?

CONCEPT:

• Pressure: The force per unit area is called pressure. It is denoted by P.
• The SI unit of pressure is the pascal (Pa).
• It is a scalar quantity because the pressure acts in all directions at a point inside a gas.
• The basic formula for pressure is given by:

\({\rm{Pressure (P)}} = \frac{{{\rm{Force (F)}}}}{{{\rm{Area (A)}}}}\)

EXPLANATION:

Given - length of cubical block (a) = 2 cm = 2 × 10^-2 m and mass of the block (m) = 2 kg

• The area of the block is 

⇒ A = a² = (2 × 10-2 )² = 4 × 10-4 m²

• The pressure exerted by the block on the ground is 

\(\Rightarrow P =\frac{F}{A}=\frac{mg}{A}\)

\(\Rightarrow P =\frac{2\times 9.8}{4\times 10^{-4}}=4.9\times 10^4 \,Nm^{-2}\)