Question

Miguel notices that on cold days his car's tire pressure light comes on but when the weather is hot the light is off. Explain why this happens using what you know about the gas laws.

Answer 1

Temperature, pressure, and volume properties of an ideal gas are related as shown in the equation below;

(P1*V1)/T1 = (P2*V2)/T2

When the environmental temperatures dropped, the gas in the tire cooled and its volume decreased. This, therefore, changed the air pressure in the tire causing it to drop. In a hot day, the gas temperature increases and the volume increases restoring pressure in the tire.