recall that the pressure in fluids causes a force normal to any surface

recall and apply the relationship between the force, the pressure, and the area in contact:

pressure (Pa) = force normal to a surface (N) ÷ area of that surface (m²)

recall that gases can be compressed or expanded by pressure changes and that the pressure produces a net force at right angles to any surface

use the particle model of matter to explain how increasing the volume in which a gas is contained, at constant temperature, can lead to a decrease in pressure

select and apply the equation:

pressure × volume = constant (for a given mass of gas at constant temperature)

describe a simple model of the Earth’s atmosphere and of atmospheric pressure, and explain why atmospheric pressure varies with height above the surface

explain why pressure in a liquid varies with depth and density

select and apply the equation to calculate the differences in pressure at different depths in a liquid:

pressure = density × gravitational field strength × depth

explain how the increase in pressure with depth in a fluid leads to an upwards force on a partially submerged object

describe and explain the factors which influence whether a particular object will float or sink