Question

If an egg person starts from rest then falls directly downward and hits the ground with a velocity of 12 m/s but their starting height was 10 m, what would their velocity be upon hitting the ground without air resistance?

Answer 1

7.2 m/s^2, 14m/s

Explanation:

Let us take the current scenario.

u = initial speed = 0

v = final speed = 12 m/s

Height of fall = 10m

Using kinematic equation, we know

$v^2 - u^2 = 2gS$

Therefore

$144 = 2g*10$

g = $144/20 m/s^2$

g = $7.2 m/s^2$ where we are not ignoring air resistance.

This is because we assume that air resistance is uniform throughout the fall.

Now, when we ignore air resistance, then the value of g will be 9.81 m/s^2.

$v^2 - u^2 = 2*g*S$

$v^2 = 2*9.81*10$

v = 14m/s