Charles' law

Charles' law states that for a gas held at constant pressure, the volume (V) occupied by the gas is directly proportional to its temperature (T). That is:


VT, or
V/T = k,
where k is a constant.


The relationship was discovered by Jacques Charles in 1787 and is a special case of the ideal gas law. It is sometimes called Gay-Lussac's law, because Joseph Gay-Lussac established it more accurately in 1882.