Pressure Formula
In daily life we see many example of pressure. We know that the tyres of car, bike getting pressurized. The best example of pressure is air filling machine. This machine has digital indicator & this indicator shows the digital reading of pressure. The machine fills the pressure to a certain value. That means force is applied to filling air into the tyres of vehicles with hand pump. This air filling machine is also used to blow the balloons.
Definition & Equation
Pressure is defined as the force exerted perpendicularly on a unit area.
Pressure = Force (F)/Area on which the force in applied (A)
Pressure = F/A —– (1)
Unit of Pressure is N/m2 or Pascal (Pa).
Unit of force is Newton (N) & unit of area is m2
So, pressure = f/A = N/m2 Pascals (pa).
From equation (1) the relation between pressure and area is inverse. That means it area is increases, pressure reduces for the same force (constant force), and if the area decreases the pressure increases for the same force.
Numericals:
(1) The force of 1000 N applied on circular disc of area 10 cm2. What would be the pressure on the surface of disc.
Given:
Force F = 1000 N
Area A = 10 cm2 = 10 × 10-4 m2
= 10-3 m2
Pressure = Force/area
= 1000/10-3
Pressure = 1.0 × 106 N/m2
(2) A force of 600 N acting on an area of 1.0m2 calculate the pressure?
Given:
Pressure =?
Force (F) = 600N
Area = (A) = 1.0m2
P = F/A
P = 600N/1.0m2
P = 600 N/m2
P = 600 Pa