200 kPa when its temperature is 20 °C (Gauge pressure is the difference between the actual pressure and atmospheric pressure). After the car has been driven at high speeds, the tire temperature increases to 50 °C. a) Assuming that the volume of the tyre does not change, and that air behaves as an ideal gas, find the gauge pressure of the air in the tire. b) Calculate the gauge pressure if the volume of the tyre expands by 10 % .