means the velocity of the train (t) relative to the ground (g) and so on with p=person.
We find the time it takes for the train to get to the hole:
Note that the subscripts for the velocities show how the velocities are measured. means the velocity of the train (t) relative to the ground (g) and so on with p=person.
The person needs to go 15m relative to the train in 2.5s
