Units (Solids, Liquids and Gases)

State the unit of pressure in the SI system.

Explain why a sharp knife cuts more easily than a blunt one, using ideas about pressure.

State what causes atmospheric pressure.

A laboratory set of Magdeburg hemispheres has a surface area of 0.04 m². The atmospheric pressure is 100,000 Pa.

State the equation that relates the pressure difference in a liquid to its density, the height of the column, and gravitational field strength.

Calculate the pressure difference at a depth of 2.5 m in a liquid of density 1200 kg/m³. Take g = 10 N/kg.

Explain why the pressure in a liquid increases with depth.

A liquid has a density of 1100 kg/m³. The pressure difference between two points is measured as 22,000 Pa. Gravitational field strength is 10 N/kg. Calculate the difference in depth between the two points.

A rectangular tank is filled with a liquid to a depth of 1.2 m. The density of the liquid is 950 kg/m³. g = 10 N/kg.

A weather map uses isobars to show regions of equal atmospheric pressure. Explain why areas where isobars are close together often experience strong winds.