Average Acceleration The average acceleration a during the time interval At, is defined as the change in velocity Av divided by the△t △t It is a vector Physics 121: Lecture 4, Pg 6Physics 121: Lecture 4, Pg 6 Average Acceleration The average acceleration a during the time interval t, is defined as the change in velocity v divided by the t It is a vector … f i f i t t v v t v a − − =   =