## Acceleration

The average acceleration of an object can be calculated using the equation:

Acceleration = Change in velocity/Time Taken

acceleration, a, in metres per second squared, m/s^2

change in velocity, ∆v, in metres per second, m/s

time, t, in seconds, s

An object that slows down is decelerating.

The acceleration of an object can be calculated from the gradient of a velocity–time graph.

The distance travelled by an object (or displacement of an object) can be calculated from the area under a velocity–time graph.

The following equation applies to uniform acceleration:

final velocity^2 − initial velocity^2 = 2 × acceleration × distance

final velocity, v, in metres per second, m/s

initial velocity, u, in metres per second, m/s

acceleration, a, in metres per second squared, m/s^2

distance, s, in metres, m

Near the Earth’s surface any object falling freely under gravity has an acceleration of about 9.8 m/s^2 .