An athlete participating in cross-country spends the afternoon practicing, and at the end is completely exhausted from all the hard word, even though their average velocity during the practice was 0 m/s. Explain how this situation is possible.

please find the answer in the explanation

Explanation:

Velocity is the distance covered in a specific direction per time taken.

And in velocity, we have final velocity V and initial velocity U.

The definition of average velocity is:

Average velocity = (V + U)/2

Since velocity involves direction, if the initial velocity U is of the same magnitude as the final velocity V and both are of opposite direction. Then,

Average velocity = (-U + V)/2

Since they are of the same magnitude,

V = U.

Therefore,

Average velocity = (-U + U)/2 = 0

v=ir = 3x15 =45 v