Question

a freight train is traveling due west at 10 miles per hour and begins to slowly pick up speed. of the train reaches a speed of 70 mph in 2 hours, what is the average acceleration of the train.

Answer 1

Since 60 mph = 88 ft/sec

10 mph = 14.7 ft/sec

70 mph = 7/6 * 88 ft/sec = 103.7 ft/sec

a = (v2 - v1) / t = (103.7 - 14.7) ft/sec / 7200 sec = .0124 ft/sec^2