Question

11. A roller coaster car is moving slowly up a long ramp to the very top of the roller coaster. It goes over the top and starts down a steep slope and it picks up speed rapidly as it rolls down an almost vertical slope. Four seconds later, at the bottom of the steep slope, its velocity is 28 m/s. The average acceleration during those 4 seconds was 6 m/s2 . What was the initial velocity of the roller coaster car as it started down the slope?

Answer 1

a = (v2 - v1) / t

a t = v2 - v1

v1 = v2 - a t

v1 = 28 m/s - 6 m/s^2 * 4 s = 4 m/s