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.

Both of them reach the lake at the same time.

Explanation:

We have equation of motion s = ut + 0.5at²

Vertical motion of James : -

          Initial velocity, u = 0 m/s

         Acceleration, a = g

         Displacement, s = h

    Substituting,

                  s = ut + 0.5 at²

                 h = 0 x t + 0.5 x g x t²

Vertical motion of John : -

          Initial velocity, u = 0 m/s

         Acceleration, a = g

         Displacement, s = h

    Substituting,

                  s = ut + 0.5 at²

                 h = 0 x t + 0.5 x g x t²

So both times are same.

Both of them reach the lake at the same time.

fgravity=10x10=100n case 1

fgravity=30x20=600n case 2

6 times more

+15-35=-20

going in opposite directions