Pressure

• It is the normal force acting on a per unit area of the surface.
• The S.I. unit of force is Pascal or N/m^2.
• It is denoted by'p'.

Pressure = Thrust/Area
and by this formula, we can get the following formulae:

1. Thrust = Pressure*Area
2. Area = Thrust/Pressure

Do You Know

There are many units of pressure, some of them are as follows:

1. 1 N/m^2 = 1 Pascal
2. 1 bar =10^5 Pascal
3. 1 atm =1.013*10^5 Pascal
4. 1 torr = 133.33 Pascal

Factors Affecting Pressure

• Pressure is directly proportional to the normal force acting. On increasing the force, the pressure increases.
• Pressure is inversely Proportional to the surface area. On increasing,the surface area, the pressure decreases.

Applications

1. Broad handles are provided in suitcase and bags.
2. Cutting edges of knife are sharp.
3. Camel is known as the ship of the desert
4. Nails and pins have pointed ends.

Do You Know

• Fluids also exert pressure.
• The gasses exert pressure on the walls of the containers.
• The pressure in the liquid increases with depth.

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