Work Done on a Gas

Work done is the transfer of energy by a force. Applying a force on a gas transfers energy to the gas particles. This increases the internal energy of the gas.

For example, let’s look at the diagram below.

1. A force is applied to push the piston by a certain distance.

2. This decreases the volume of the gas container

  • There is now less space between the gas particles, as the number of gas particles has not changed

3. The gas particles now move around faster, so they have higher kinetic energy.

The temperature of a gas is related to the average kinetic energy of the particles. As the kinetic energy of the gas particles has increased, the temperature of the gas has also increased.

In an expandable container, a gas will do work, so it will lose kinetic energy. Therefore, the temperature will decrease.