# What is Charles' law formula?

Jun 27, 2014

The physical law that the volume of a fixed mass of gas held at a constant pressure varies directly with the absolute temperature.

This law states that the volume of a given amount of gas ,at a constant pressure gas varies with its temperature

or simply we can say that the volume of gas changes with its temperature. At a higher temperature , a gas will take up more volume ( expands) , at a lower temperature, a gas will take up lesser volume or it contracts.

Let us suppose that we have a given amount of gas enclose in a balloon, the temperature of the gas is ${T}_{1}$ (Kelvin) , and it takes up the volume ${V}_{1}$ (Liter). If the Temperature is changed to a new value called ${T}_{2}$ , then the volume changes to ${V}_{2}$.

as per the law the ratio of Volume / temperature stays the same, if one increases , the other decreases but the ratio does not change.

${V}_{1}$ / ${T}_{1}$ = k ......(a)

${V}_{2}$ / ${T}_{2}$ = k ......(b)

equating the two equations (a) and (b)

${V}_{1}$ / ${T}_{1}$ = ${V}_{2}$ /${T}_{2}$

or

${V}_{1}$ . ${T}_{2}$ = ${V}_{2}$ . ${T}_{1}$