A student seals the end of a plastic syringe.
The syringe contains 60 cm3 of air at a pressure of 100 kPa.
The student pushes the plunger in slowly. The volume of the air decreases. The temperature of the air does not change.
State what happens to the pressure of the air.
The student pushes the plunger in until the volume of the air is 40 cm3.
Use the equation: pressure×volume=constant\text{pressure} \times \text{volume} = \text{constant}pressure×volume=constant
Calculate the new pressure of the air in kPa\text{kPa}kPa.
Air can be compressed into a smaller volume, but water cannot.
Explain why, in terms of particles.
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.