Acceleration

$a_{avg}=\dfrac{\Delta v}{\Delta t}=\dfrac{v_f-v_0}{t_f-t_0}$
where $$v$$ is velocity, and $$t$$ is time. Acceleration is a vector in the same direction as the change in velocity, $$\Delta v$$. Since velocity is a vector, it can change either in magnitude or in direction. Acceleration is, therefore, a change in either speed or direction, or both. The “acceleration due to gravity” is also equal to the “gravitational field”. Equivalence of inertial and gravitational mass.