# Homework Help: Grade 11 Physics: A subway train

1. Sep 26, 2010

### soniaFB

A subway train starts from rest at a station and accelerates at the rate of 2.0m/s^2 for 10s. It runs at a constant speed for 30s, and then decelerates at 2.4m/s^2 until it stops at the next station.

Find the total distance between the stations and the average speed of the train.

2. Sep 26, 2010

### Thefox14

Well first I'd see that you need to break this down into 3 separate problems.
1) Train accelerating at the rate of 2.0m/s^2 for 10s
2) Going at constant speed for 30s
3) Decelerating at 2.4m/s^2 until it stops

Notice that the problems involving an acceleration have constant accelerations, so you can you all of the kinematic equations to solve for the distance. After that, the last part should be fairly simple