A cyclist uses a bicycle pump to pump up a tyre.
The cyclist pushes the handle of the pump in quickly many times. The pump gets warm.
Explain why the temperature of the air in the pump increases when the handle is pushed in quickly.
The cyclist then pushes the handle in slowly.
Suggest why the temperature of the air increases less.
When the handle is pulled out, the air in the pump has a volume of 150 cm3 and a pressure of 100 kPa.
The valve to the tyre opens when the pressure of the air in the pump reaches 250 kPa.
Use the equation: pressure×volume=constant\text{pressure} \times \text{volume} = \text{constant}pressure×volume=constant
Calculate the volume of the air in the pump when the valve opens. Assume the temperature of the air does not change.
When the handle is pushed in quickly, the valve opens at a larger volume than your answer to (c).
Explain why.
50 exam-style questions on OCR GCSE Physics 1.3 Pressure, covering 1.3.1 Molecular motion, temperature and gas pressure, 1.3.2 Gas pressure at constant volume, 1.3.3 Compressing and expanding gases, 1.3.4 Gas volume and pressure at constant temperature, 1.3.5 Doing work on a gas, 1.3.6 The Earth's atmosphere and atmospheric pressure, 1.3.7 Atmospheric pressure and height, 1.3.8 Floating and sinking, 1.3.9 Pressure in liquids and upthrust, and 1.3.10 Pressure differences with depth. Each one has a worked solution and a mark scheme showing where the marks go.