Grade 11 Physics: A subway train

AI Thread Summary
The discussion focuses on calculating the total distance a subway train travels between two stations and its average speed. The train accelerates at 2.0 m/s² for 10 seconds, maintains a constant speed for 30 seconds, and then decelerates at 2.4 m/s² until it stops. To solve the problem, it is essential to break it down into three segments: acceleration, constant speed, and deceleration. Kinematic equations can be applied to determine the distance for the acceleration and deceleration phases. The final calculations will yield the total distance and average speed of the train.
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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.
 
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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
 
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