Question

Two trains approach each other on parallel tracks. Each has a speed of 95 kph relative to the ground. If they are initially 8.5 km apart, how long will it be before they reach one another.

Explanation please!

Answer 1

Answer: 2.83 minutes

Step-by-step explanation:

It is understood that trains are approaching. That is, they have speeds of equal magnitude but opposite. When train A travels x meters northbound, then train B travels the same distance southbound.

Therefore trains approach at a speed of:

`V = 95 +95 = 190\ km / h`

Then:

`V = (x)/(t)\\\\t = (x)/(V)`

Where x is the distance between the trains

`x = 8.5\ km`

So the time in which both trains meet is:

`t =(8.5\ km)/(180\ (km)/(h))\\\\t=0.04722\ hours`

This is:

`0.04722*(60\ minutes)/(1\ hour) = 2.83\ minutes`

How long will it be before they reach one another ?

2.83 minutes