Newton's second law - A force is caused by an acceleration acting on an object.
The most common form of acceleration is gravity. All objects are pulled towards the earth by gravity. Gravity acting on a mass produces the effect commonly known as weight which is really a type of force.
Newton's second law can be written as a mathematical equation.
force = mass x acceleration
f = m x a or f = ma
Force is a push or pull which is applied to an object. Force is measured in newtons (N).
Mass is the mass or weight of the object to which the force is being applied. Mass is measured in kilograms (kg).
Acceleration is any change in the speed or velocity of the object, ie speeding up or slowing down. Acceleration is measured in metres per second per second (m/s2).