The Pressure Law (Edexcel IGCSE Physics: Double Science)

• If the volume V of an ideal gas is constant, the pressure law is given by:

P ∝ T

• This means the pressure is proportional to the temperature

• The relationship between the pressure and (Kelvin) temperature for a fixed mass of gas at constant volume can also be written as:

• Where:
  • P₁ = initial pressure (Pa)
  • P₂ = final pressure (Pa)
  • T₁ = initial temperature (K)
  • T₂ = final temperature (K)

Pressure law graph representing temperature (in °C) directly proportional to the volume