2006-08-15 17:51:28 · 5 answers · asked by nokia 6 1 in Science & Mathematics ➔ Physics
Pressure is the force exerted by the atoms on the walls of the container. More the force more is the pressure. When the medium in the container is heated the atoms move faster exerting more force on the falls thus increasing the pressure. Similarly when more atoms are admitted into the container the force increases so is the pressure
2006-08-15 18:02:13 · answer #1 · answered by PBVenkat 2 · 0⤊ 0⤋
Pressure is force per unit area.
In the case of solids, under the action of gravity the solid is pulled down.
Each molecule of the solid is pulled down. But we can replace all the forces as if they were acting on a single point namely the center of gravity.
If the object has a base area ‘A’ and if it is placed over some surface the force (the weight) is acting over the whole area A. The whole area ‘A’ is pressed down.
Now the pressure at any point inside this area ‘A’ is “weight / (area ‘A’)”
Generally we don’t require the pressure in the case of a solid and we are interested only in the weight (force exerted by) of the solid substance.
In the case of a liquid and gas, it is different. A liquid requires a container to keep it. The liquid exerts forces not only on the bottom surface but also along the sides of the container. A gas exerts force in all directions.
Therefore, the weight of the gas or liquid is not needed for us; but the force at each point is needed.
Hence in the case of liquid and gas we think of a small area around a point at which we want to find the force. Then the pressure is found by dividing the force by that small area around the point.
Though this is the method to calculate the pressure, in actual practice, it is the pressure that is easily found out or easily measured than the actual force.
For example, the pressure at the bottom of a liquid depends on the height of liquid column over that point.
The total normal force is then easily calculated by the product of pressure and area.
2006-08-16 01:41:27 · answer #2 · answered by Pearlsawme 7 · 0⤊ 0⤋
Pressure is a distributed force.
If you put a cube with 1 ib weight on a table then the presure between the object is 1 lb/sq fit. You can extent this to any liquid and gas as well
2006-08-16 01:43:54 · answer #3 · answered by Dr M 5 · 0⤊ 0⤋
The pressure on Earth is fourteen atmospheres at Sea Level.
Other than that, you are putting way too much pressure upon yourself!
2006-08-19 16:15:43 · answer #4 · answered by Anonymous · 0⤊ 0⤋
PV = nRT
P = nRT/V
2006-08-16 00:56:39 · answer #5 · answered by Picture Taker 7 · 1⤊ 0⤋