The equation for pressure is the force divided by the area whereby the pressure is applied. Back this measure is straightforward once a heavy is advertise on a solid, the instance of a solid advertise on a liquid or gas requires that the liquid be border in a container.

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The pressure can likewise be produced by the weight of one object.

Questions you may have actually include:

What is the pressure as soon as a heavy pushes on another solid? What happens as soon as a solid pushes on a confined fluid? What happens once the force comes from gravity?

This lesson will answer those questions. Useful tool: units Conversion


Pressure of hard on a solid

When you apply a force to a heavy object, the pressure is characterized as the force applied divided by the area that application. The equation for push is:

P = F/A

where

P is the pressure F is the applied force A is the surface area wherein the force is applied F/A is F separated by A

For example, if you press on an object with your hand with a force of 20 pounds, and also the area of your hand is 10 square inches, climate the push you are exerting is 20 / 10 = 2 pounds every square inch.

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Pressure amounts to Force divided by Area

You can see the for a provided force, if the surface area is smaller, the push will it is in greater. If you use a larger area, you are spreading out the force, and the press (or pressure per unit area) becomes smaller.

Solid pressing on border fluid

When a fluid or gas is border in a container or cylinder, you can create a press by applying a force with a heavy piston. The pressure produced in the cylinder equates to the force used divided by the area that the piston: P = F/A.

In a border fluid—neglecting the result of heaviness on the fluid—the push is the same throughout the container, pushing equally on every the walls. In the situation of a bicycle pump, the pressure developed inside the pump will certainly be sent v the hose right into the bicycle tire. Yet the waiting is still all confined.

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Pressure is in all directions in a fluid

Increasing the pressure will increase the pressure inside the cylinder.

Caused through gravity

Since the weight of things is a pressure caused through gravity, we deserve to substitute weight in the pressure equation. Thus the press (P) caused by the load (W) of an item is the weight split by the area (A) wherein the load is applied.

P = W/A

If you ar a solid object on the floor, the press on the floor over the area of call is the weight of the object separated by the area ~ above the floor.

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Pressure equates to Weight divided by Area

Example through shoes

A an excellent example of how a force on little area can result in a very high pressure is viewed in women"s shoes with high spiked heels. These varieties of shoes can reason damage to some floors as result of the an extremely high push on the floor in ~ the heel.

An mean shoe distributes the load of the human being over 20 square inches. Thus, a 100-pound person applies 100/20 = 5 pounds every square customs on the floor.

Since a spike-heel is only 0.25 square inches, the 100-pound person would be using 100/0.25 = 400 pounds every square customs on the floor at the heel! In some cases, the is adequate to damages the floor.

Fluid weight

If you placed a fluid in a container, the weight of the liquid would be pushing on the bottom the the container comparable to the of the load of a solid object. The press on the bottom that the container would be the exact same as if the load was native a solid:

P = W/A.

The only difference is that pressure in a liquid goes in all directions. So the press on the political parties at the bottom would certainly be the same.

Gases and also liquids exhibit pressure due to their load at every suggest in the fluid.

Summary

Pressure is the force on things that is spread over a surface ar area. The equation for pressure is P = F/A. Pressure can be measured because that a solid is pushing on a solid, however the situation of a solid advertise on a fluid or gas requires that the fluid be confined in a container. The pressure can also be created by the load of one object.

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