A railroad engine moves forward along a straight section of track for a distance of 80 m due west at a constant speed of 5 m/s. It then reverses its direction and travels 20 m due east at a constant speed of 4 m/s. The time required for this deceleration and reversal is very short due to the small speeds involved.
a. What is the time required for the entire process?
b. Sketch a graph of average speed versus time for this process. Show the deceleration and reacceleration upon reversal as occurring over a very short time interval.
c. Using negative values of velocity to represent reversed motion, sketch a graph of velocity versus time for the engine.
d. Sketch a graph of acceleration versus time for the engine.