A flexible-walled, gas-filled research container is submerged in a deep water tank.
Explain, in terms of the momentum of the molecules, why there is a pressure exerted on the inner surface of the container.
The volume of the gas in the container is initially 480 cm3480\text{ cm}^3480 cm3 and the pressure of the gas is 1.2×105 Pa1.2 \times 10^5\text{ Pa}1.2×105 Pa.
The container is pulled down vertically into the water tank by a motorized cable. The descent is rapid enough that the temperature of the gas inside does not change during this movement.
Calculate the volume of the gas in the container when the external pressure squeezes the container until the gas pressure reaches 1.6×105 Pa1.6 \times 10^5\text{ Pa}1.6×105 Pa.
When the container is held stationary at the bottom of the tank, the temperature of the gas begins to decrease due to thermal contact with the cold deep water. Explain why the volume of the gas in the container decreases as the temperature of the gas decreases.
321 exam-style questions on CIE IGCSE Physics 2.1 Kinetic particle model of matter, covering 2.1.1 States of matter and changes of state, 2.1.2a Particle structure and motion in solids, liquids and gases, 2.1.2b Gas pressure and particle collisions, 2.1.2c Brownian motion, 2.1.3a The absolute scale of temperature, and 2.1.3b Pressure, volume and temperature of a gas. Each one has a worked solution and a mark scheme showing where the marks go.