Answer:
810 000 ft
Explanation:
First we convert 90 mi/h to ft/s
90 mi/h = 90 mi/h * 5280 ft/1 mi * 1 hr/3600 s = 132 ft/s
To find the distance covered for the train to travel from rest to 132 ft/s we use an equation of linear motion based on the values we have and the measurement we are supposed to find:
x = 0.5at² [the term for initial velocity is omitted because the train starts
form rest]
x = 0.5 * 4 ft/s² * (450 s)² = 405 000 ft
The maximum distance will be twice this because the train must reach the maximum velocity and again decelerate to zero.
distance covered = 2 * 405 000 ft = 810 000 ft =
