Work on a Gas (HT only)
- Work is the transfer of energy by a force
- Doing work on a gas involves a transfer of energy
- This increases its internal energy and can also cause an increase in the temperature
- Work can be done on a gas by compression
- A force is used to push a piston by a certain distance
- This decreases the volume of the gas
- The molecules move around faster and therefore have a higher kinetic energy
- This increase in kinetic energy increases its temperature
To compress the above gas, a force must be used to move the piston a certain distance. This involves doing work
- If a gas is allowed to expand, the gas will do work instead
- This causes the gas to lose energy, which results in a decrease in temperature