Answer:
11.18 m/s.
Step-by-step explanation:
From the question given above, the following data were obtained:
Mass (m) = 800 kg
Height (h) = 20 m
Energy (E) = 50000 J
Velocity (v) =?
The velocity of the roller coaster can be obtained as follow:
E = ½mv²
50000 = ½ × 800 × v²
50000 = 400 × v²
Divide both side by 400
v² = 50000 / 400
v² = 125
v = √125
v = 11.18 m/s
Therefore, the velocity of the roller coaster is 11.18 m/s.