To determine the velocity of the roller coaster as it moves down, we use the kinematic equation which is expressed as 2gy = vf^2 - v0^2 where g is the gravitational acceleration, y is the elevation of the roller coaster, vf and vo are the final and initial velocity. We calculate as follows:
2gy = vf^2 - v0^2
Since it starts at rest, v0 is zero.
2gy = vf^2
vf = √2gy
vf = √2(9.8)(101)
vf = 44.5 m/s ----> option B
