Newton's Laws of Motion

Newton's first law of motion states that if all the forces acting on an object are in 'equilibrium', the object in question will remain at the speed/ velocity it is heading;This includes stationary. So basically, if all the forces acting on a moving car are of equally balanced values then the car will remain at that speed until a resultant force is applied.

Newton's second law of motion states that if there is a resultant force, there will be a change in velocity, i.e. acceleration. In addition, this law highlights that the acceleration is proportional to the resultant force.

Resultant force (F) = Mass (m) x Acceleration (a)
F = ma 

Newton's third law of motion relates to the idea that if body A exerts a force on body B, then body B will exert a force of body A of the same magnitude but an opposite direction.

For example, the Earth exerts a gravitational force of 10N on a rock, so the rock exerts an upwards gravitational force of 10N on the Earth.