Charles' Law
Key Stage 5
Meaning
Charles' law states that for a fixed mass of an ideal gas at constant pressure, its volume is directly proportional to its absolute temperature.
About Charles' Law
- Charles' Law is expressed mathematically as 𝑉∝𝑇.
- Demonstrates the relationship between volume and temperature of gases.
Assumes the gas behaves ideally and pressure remains constant. Charles' law can be derived from the ideal gas law. Important in understanding the behaviour of gases under different temperature conditions. Used in various applications involving gases, such as ballooning and air conditioning. Helps in predicting the expansion or contraction of gases with temperature changes.
Formula
\(T\propto V\)
\(\frac{V}{T}=constant\)
Where,
V is the volume of the ideal gas,
and
T is the temperature of the ideal gas
When there is a change of temperature and volume of a known amount of an ideal gas at constant pressure the following formula can be used\[\frac{V_1}{T_1}=\frac{V_2}{T_2}\]
Where the number represents before and after the change.
Examples
A balloon expands when heated due to the increase in volume as per Charles' law. Hot air balloons rise because the heated air inside expands, making it less dense than the surrounding air.