Final answer:
The air pressure inside car tyres increases during summer as the temperature increases, leading to thermal expansion of the air. The tyre walls limiting expansion and increased heat from sunlight contribute to this pressure rise. Manufacturers recommend tyre pressures based on cold temperatures.
Step-by-step explanation:
Air Pressure Increase in Car Tyres
The air pressure in car tyres increases during summers primarily due to the thermal expansion of air. When a car is driven, the tyres flex and their temperature increases, leading to an increase in air pressure inside the tyre. This phenomenon is explained by the basic gas law principles, where the volume of a gas is initially directly proportionate to the amount of air until the tyre is nearly at full size. Then, as the tyre walls limit expansion, any further air increases the pressure. On warm days, tyres exposed to sunlight get even hotter, and the air inside expands, further elevating the pressure. Manufacturers specify optimal tyre pressure based on cold temperatures, so extra caution is needed during summer to ensure tyres are not overinflated.