A unit of measurement describes one unit of a quantity. Units of measurement can be imperial or metric. They can be converted using conversion factors.
Pressure indicates the amount of forceA push or a pull. The unit of force is the newton (N). being exerted per unit area.
The units for pressure can be quite complex depending on whether you are working in imperial or metric units. Scientists might use pascalUnit of pressure. Pascal (Pa), eg normal atmospheric pressure is 1.01x105 Pa. as the unit for pressure but in GCSE Maths it is likely that compound units will be used. For example, the air pressure of a basketball is about 8 pounds per square inch. Other compound units that might be used are kg/m2 or g/cm2. Sometimes you might even see N/m2, which means newtonUnit of force named after British scientist Isaac Newton (1642-1727), eg the frictional force on the boat is 20,000 N. per square metre.
Notice how all the compound units have one thing in common: they are all per square inch or /m2 or /cm2. All are saying 鈥減er unit area鈥 and so the calculation will always involve dividing by the area.
Example
The surface area of a pair of skis is 0.25 m2. A skier has a mass of 70 kg. How much pressure, in kg/m2, does the skier exert on the snow?
The units are telling us to divide the number of kg by the number of m2.