A moving locomotive problem normally poses the challenge of finding out the time taken, the speed, or the distance covered while a particular object pass another. The moving locomotive can be a train, a car, a flight etc. and the objects can be a truck, a man, a platform, a pole, a bridge, a tunnel, a stationary train, a moving train etc.

* A moving locomotive is said to have crossed or passed an object (stationary or moving) only when the total length of the moving locomotive crosses the total length of the object.*

For instance, for a train to cross an object,

Distance covered by the train = length of train + length of object.

### Important Facts, Tips and Shortcuts for Calculation

- km/hr. to m/s conversion:
- x km/hr = (x × ) m/s

- m/s to km/hr. conversion:
- x m/s = (x × ) km/hr

- Speed =
- Suppose two objects are moving in the same direction at u m/s and v m/s, where

u ˃ v, then their relative speed = (u – v) m/s. - Suppose two objects are moving in opposite directions at u m/s and v m/s, then their relative speed = (u + v) m/s.

*“For detailed theory, refer the book “CSIR-NET General Aptitude – A New Outlook”*