Changing gas pressure - Higher
Force exerted over an area. The greater the pressure, the greater the force exerted over the same area. can be increased by:
- increasing the A measure of the average kinetic energy of particles in a substance. - this increases the force of each collision
- decreasing the The volume of a three-dimensional shape is a measure of the amount of space or capacity it occupies, eg an average can of fizzy drink has a volume of 330 ml. - this increases the number of collisions per second
Boyle concluded that volume could only be inversely proportional to pressure for a fixed mass of gas and at a constant temperature if gases contained particles that were moving around. This and subsequent discoveries triggered the The process that transformed manufacturing from handmade to machine-made, mass-produced goods using water, steam and coal power transported by canal, rail and steamship. Britain was the first country to have an Industrial Revolution. in the 18th century.
Forces applied to the particles in a gas result in a transfer of The capacity for doing work..
When a person presses a piston down on a column of gas, they apply a A push or a pull. The unit of force is the newton (N). that moves the piston a certain distance. They have done Energy transferred by a force. Work done = force × distance moved in the direction of the force. on the gas by compressing it.
work done = force × distance
Since the volume of the gas has decreased, the pressure increases because the A general term for a small piece of matter. For example, protons, neutrons, electrons, atoms, ions or molecules. are moving in less space and collide more often. The temperature of the gas is not fixed in most applications and the increased pressure leads to an increase in temperature. This is because the temperature is a measure of the average Energy which an object possesses by being in motion. of particles - the increase in the internal energy of the gas (as kinetic energy of the particles) means that the temperature must increase.
This process explains why a bicycle pump gets warm when it is used to inflate a tyre.