a = (v_f - v_i) / t

where:

* a is acceleration

* v_f is final velocity

* v_i is initial velocity

* t is time

Explanation:

* Acceleration is the rate of change of velocity over time.

* Final velocity (v_f) is the velocity of an object at the end of a given time interval.

* Initial velocity (v_i) is the velocity of an object at the beginning of a given time interval.

* Time (t) is the duration over which the velocity changes.

Units:

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

* Velocity is measured in meters per second (m/s).

* Time is measured in seconds (s).

Example:

A car starts from rest (v_i = 0 m/s) and accelerates to a final velocity of 20 m/s in 5 seconds. What is the car's acceleration?

* a = (v_f - v_i) / t

* a = (20 m/s - 0 m/s) / 5 s

* a = 4 m/s²

Therefore, the car's acceleration is 4 m/s².