# Why are we taking out relative velocity here??? And in the second step why have we taken the speed of the cycle to be V and not 18 km/h ..????? With this question.. I hope u must have understood my problem..ie I am not getting the logic of WHERE to and HOW to apply relative motion..????:"( Pls experts understand this and guide me!!

There are two velocities, one that of the cyclist and another one that of the bus.In such cases we need to take the relative velocity.

If both are in same direction we subtract the velocities and if they are in opposite direction we add them.

**18 is the time taken for the bus to move in same direction as the cyclist. It is not the speed of the bu**s.

Regards..

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