physics forces and motion

force

a push or pull on an object that can cause a change in speed, direction or shape measured in newtons (N)

contact force

force between two objects that are touching

non-contact forces

force between two objects that are not touching

balanced forces

opposite forces of equal size

resultant force

the overall force acting on an object

friction

force that always acts to oppose motion or attempted motion

drag

friction force caused when an object moves through air

average speed

the rate of change of distance travelled m/s

acceleration

the rate of change of speed m/s²

deceleration

a decrease in speed

constant speed

speed remains the same over a period of time

weight

the downward force caused by gravity on an object, measured in Newtons (N)

mass

the amount of matter that makes up an object, measured in kilograms

unbalanced forces

opposite forces of unequal size