An apple falls from a tree from a height of 5 m for 2 seconds. Determine its speed at the moment of impact.

Given:

h = 5 meters – the height from which the apple falls;

t = 2 seconds – the period of time during which the apple falls.

It is required to determine v (meter per second) – the speed of the apple at the moment it hits the ground.

Let’s find the acceleration with which the apple falls:

h = a * t2 / 2, hence:

a = 2 * h / t2 = 2 * 5/22 = 10/4 = 2.5 m / s2.

Then the speed of the apple at the moment of hitting the ground will be equal to:

v = a * t = 2.5 * 2 = 5 meters per second.

Answer: the speed of the apple at the moment of hitting the ground is 5 meters per second.