Question

A 200 kg roller coaster car is located at the top of a hill where the height is 30 m. What is the velocity when it reaches the bottom of the hill?

5.5 m/s
11.2 m/s
16.7 m/s
24.2 m/s

Answer 1

Use energy conservation (mgh = 1/2 m v^2). Mass cancels, so v = sqrt(2gh).

v = sqrt(2·9.8·30) = sqrt(588) ≈ 24.3 m/s.

Closest choice: 24.2 m/s (assuming no friction).