Acceleration is the rate at which velocity changes over time. It is calculated by dividing the change in velocity by the change in time:

```

Acceleration = (Final Velocity - Initial Velocity) / (Final Time - Initial Time)

```

Or

```

a = (v_f - v_i) / (t_f - t_i)

```

Where:

* Acceleration (a) is measured in meters per second squared (m/s²)

* Final Velocity (v_f) is the velocity of the object at the end of the time interval

* Initial Velocity (v_i) is the velocity of the object at the beginning of the time interval

* Final Time (t_f) is the time at the end of the time interval

* Initial Time (t_i) is the time at the beginning of the time interval