Answer:
14 m/s
Explanation:
The child is falling due to constant gravitational acceleration.
This means we can use a kinematics equation to relate:
First, we can list our knowns (givens):
We are solving for:
This means we can use the combined kinematics equation to relate the knowns and unknowns:
where:
Plugging in the known values, we get:
[tex]v_f^2 = (0\text{ m/s})^2 + 2\!\left(9.8\text{ m/s}^2\right)\!(10\text{ m})[/tex]
Solving for [tex]v_f[/tex], we get:
[tex]v_f^2 = 196\text{ m}^2/\text{s}^2[/tex]
[tex]v_f = \sqrt{196\text{ m}^2/\text{s}^2}[/tex]
[tex]\boxed{v_f = 14\text{ m/s}}[/tex]
So, the child is moving 14 meters per second right before he hits the water.