If a body after travelling some distance comes back to its starting point then-

Concept:

• Displacement (S’): The minimum path length between starting point to final point is called displacement.

• Displacement is a vector quantity.
• It can be positive, negative or zero.
• The SI unit of displacement is meter (m).

Explanation:

• An object comes back to its starting point after travelling some distance then the displacement becomes zero.

\(Average\;Velocity = \frac{{Displacement}}{{Time\;Taken}}\)

\(Average\;Velocity = \frac{0}{t}\)

So, average velocity = 0.