Question

A boy steps off the end of a 3.00 m high diving board and drops to the water below. Using 9.8 m/s2 as acceleration due to earth's gravity, how many seconds does it take for him to reach the water? Only enter the number, not the units.

Answer 1

Answer:

t = 0.78 s

Explanation:

Given that,

The height of a diving board, h = 3 m

We need to find the time it take for him to reach the water. Let the time is t./

Using second equation of motion as follows :

$h=ut+\dfrac{1}{2}at^2$

u is initial velocity, u = 0 and a = g

So,

$h=\dfrac{1}{2}gt^2\\\\t=\sqrt{\dfrac{2h}{g}} \\\\t=\sqrt{\dfrac{2\cdot3}{9.8}}\\\\t=0.78\ s$

So, it will take 0.78 seconds to reach the water.