How far to the nearest meter can a sprinter running at 9 m/s, travel in the time it takes a rock to fall 27 m?

How far to the nearest meter can a sprinter running at 9 m/s, travel in the time it takes a rock to fall 27 meters?





I can't think of the formula to use for this? Thanks.|||There are two formulae not one.


How long does the rock take to fall?


s = 1/2 g t^2


t = sqrt( 2s/g)


= sqrt( 54 / 10)


= 2.3 s





And of course at 9 m/s the sprinter will move 9 * 2.3 m ( assuming they are already at top speed when the rock starts to fall. )