Pressure

• Pressure is defined as the force per unit area. The SI unit of pressure is pascal (Pa).

• Some very important and useful devices such as syringes, dropper, drinking straw, etc., work on the principles of pressure.
• Force exerted per unit area is called pressure.
• Liquid and gases also exert pressure in all directions.
• Pressure exerted by air is called atmospheric pressure.

Variation of Pressure with Area:

• Increasing the area over which a particular force acts decreases the pressure produced.
• Decreasing the area over which a particular force acts increases the pressure produced. The pointed end of high-heeled shoes exerts a greater pressure than the flat end.