Why does the pressure of a fixed mass of gas increase when its volume is decreased at constant temperature?
The molecules move faster, so they hit the walls with a greater force.
The molecules are squashed, so each one becomes smaller and faster.
The molecules are closer, so they collide with each other more often.
The molecules travel a shorter distance, so they hit the walls more often.
40 exam-style questions on AQA GCSE Physics 3.3 Particle model and pressure, covering 3.3.1 Particle motion in gases, 3.3.2 Pressure in gases, and 3.3.3 Increasing the pressure of a gas (HT only). Each one has a worked solution and a mark scheme showing where the marks go.