Answer:
When the two bodies are moving in opposite direction
Explanation:
The relative velocity of two bodies is found by adding the velocity of one body to the other body when the two bodies are moving in opposite direction
For example, if one body is moving towards the right direction at 5.0 km/hr and the other body is moving left at 1.0 km/hr, the relative velocity of the body moving right relative to the other moving left is given as 5.0 + 1.0 = 6.0 km/hr.
Relative velocity can be experienced when moving up along on an escalator relative to the visible side drive mechanism going down.
