# What is Pressure

The pressure is thrust per unit area, hence it is directly proportional to thrust and inversely proportional to area.

The units used for pressure is pounds per square inch, Newtons per square meter, or Pascals. Atmosphere, bar, torr, and meters sea water are the other units that are used for expressing pressure.

Pascal is the SI unit of pressure and it is a derived unit. Following is the equation that is used for expressing pressure:

 $$P=\frac{F}{A}$$

Where,

• P is the pressure
• F is the force acting per unit area
• A is the unit area

The interesting part about pressure is that pressure is a scalar quantity that is it has only magnitude but no direction. Pressure can be either a positive or negative value.

Everyday examples of pressure are:

• The working of the vacuum cleaner is an example of pressure. The fan inside the vacuum creates a low-pressure region which makes it easy to suck the dust particles inside the vacuum.
• Using a knife for cutting is another example of pressure. The area exposed from the knife is small but the pressure is high enough to cut the vegetables and fruits.