Answer:
24.85 m/s.
Step-by-step explanation:
PE = mgh = 250 kg x 9.81 m/s^2 x 550 m = 1,358,725 J
PE' = mgh' = 250 kg x 9.81 m/s^2 x 125 m = 308,062.5 J
PE = KE
1,358,725 J = 0.5mv^2
Solving for v, we get:
v = sqrt(2PE/m) = sqrt(2 x 1,358,725 J / 250 kg) = 59.15 m/s (rounded to two decimal places)
PE' + KE' = PE + KE
Since the cart starts from rest at the top of the incline, KE = 0. Therefore:
PE' = KE'
mgh' = 0.5mv'^2
Solving for v', we get:
v' = sqrt(2gh') = sqrt(2 x 9.81 m/s^2 x 125 m) = 24.85 m/s (rounded to two decimal places)
Therefore, the speed of the cart at a height of 125 m above the bottom of the incline is 24.85 m/s.