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In the design of a rapid transit system, it is necessary to balance the average speed of a train against the distance between stops. The more stops there are, the slower the train’s average speed. To get an idea of this problem, calculate the time it takes a train to make a 9.0-km trip in two situations: (a) the stations at which the trains must stop are 1.8 km apart (a total of 6 stations, including those at the ends): and (b) the stations are 3.0 km apart (4 stations total). Assume that at each station the train accelerates at a rate of 1.1 m/s2 until it reaches 95 km/h. then slays at this speed until its brakes are applied for arrival at the next station, at which time it decelerates at −2.0 m/s2. Assume it stops at each intermediate station for 22 s.
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