A diver breathes out a bubble of air deep under water.
At this depth, the bubble has a volume of 3.0 cm3 and the pressure of the air in the bubble is 250 kPa.
The bubble rises to the surface, where the pressure is 100 kPa. The temperature and mass of the air in the bubble stay the same.
Calculate the volume of the bubble at the surface.
Use the equation
P1×V1=P2×V2P_1 \times V_1 = P_2 \times V_2P1×V1=P2×V2
Explain why the volume of the bubble increases as it rises.
The diver's air tank contains 0.012 m3 of air at a pressure of 20 000 kPa20\,000\ \text{kPa}20000 kPa.
Calculate the volume this air would have at a pressure of 100 kPa. The temperature of the air stays the same.
The diver uses 0.030 m3 of air each minute, measured at a pressure of 100 kPa.
Calculate how many minutes the air from (c) would last.
Use your answer to (c).
108 exam-style questions on Edexcel GCSE Physics 14.3 Gas pressure and temperature, covering 14.3.1 Gas pressure and particle motion, 14.3.2 Temperature and pressure at constant volume, 14.3.3 Absolute zero and the kelvin scale, 14.3.4 Compressing and expanding gases, 14.3.5 Volume and pressure at constant temperature, and 14.3.6 Doing work on a gas. Each one has a worked solution and a mark scheme showing where the marks go.