Average velocity is the physical quantity which describes how fast an object is moving in a certain period of time. Average velocity is a vector quantity since it has both magnitude and direction. The formula used to find the average velocity of an object travelling a certain distance from one point to another point is the change in displacement with respect to the change in time. It is also given by the formula, total displacement over total time taken if the object covers different distances in different intervals of time.
Example 1: What is the average velocity of an object if the initial displacement of the object is 5m and the final displacement is 35m in a time interval of 10secs?
Average velocity of an object, vavg = (change in displacement)/ (change in time)
This implies, average velocity, vavg = (df – di)/ (change in time)
In the given question, final displacement = df = 35m
And initial displacement, di = 5m
This gives: vavg = (35 – 5)/ (10) = 20/10 = 2m/sec
Hence the average velocity of the given object, vavg = 2m/sec
Example 2: What is the average velocity of an object if the initial velocity of the object is 20m/sec and the final velocity of the object is 65m/sec?
Average velocity of the object, vavg = [(final velocity) + (initial velocity)/ 2]
Average velocity, vavg = (65 + 20)/ 2 ==> vavg = 85/2
This gives, vavg = 42.5m/sec
Therefore the average velocity of the object, vavg = 42.m/sec