1. Change in velocity: This is the difference between the final velocity and the initial velocity of the object. You can express it as:

- Δv = v_f - v_i (where Δv is the change in velocity, v_f is the final velocity, and v_i is the initial velocity)

2. Time interval: This is the amount of time it takes for the velocity to change.

Formula for acceleration:

Acceleration (a) is calculated by dividing the change in velocity (Δv) by the time interval (Δt):

a = Δv / Δt

Units:

- Acceleration: meters per second squared (m/s²)

- Velocity: meters per second (m/s)

- Time: seconds (s)

Example:

If a car accelerates from rest (v_i = 0 m/s) to a final velocity of 20 m/s in 5 seconds, then:

- Δv = 20 m/s - 0 m/s = 20 m/s

- Δt = 5 s

- a = 20 m/s / 5 s = 4 m/s²