James and John dive from an overhang into the lake below.James simply drops straight down from the edge.John takes a running start and jumps with an initial horizontal velocity of 25 m/s.Compare the time it takes each to reach the lake below if there is no air resistance.
A)James reaches the surface of the lake first.
B)John reaches the surface of the lake first.
C)James and John will reach the surface of the lake at the same time.
D)Cannot be determined without knowing the mass of both James and John.
E)Cannot be determined without knowing the weight of both James and John.

Question

Quizplus · Accepted Answer

Since there is no air resistance, the only force acting on both James and John is gravity, which causes them to accelerate downward at the same rate of 9.8 m/s2. This means that the time it takes for both to reach the surface of the lake will only depend on the height of the overhang, and not on their initial velocities or masses. Therefore, James and John will reach the surface of the lake at the same time.

James and John Dive from an Overhang into the Lake