Question

Relative speed two trains passing each other

Answer 1

If both trains are moving in same direction then subtract the speeds
And if trains are in opposite direction then add the speed

Let take an example
If train a is moving with 100km/h
And train b is moving with speed 60.
Both going opposite to each other

So relative speed =100+60=160km/h
If in same direction then
Relative speed =100-60=40 km /h