Question

The body was released to fall freely from a height of 100 m above the Earth's surface. Determine its speed just before hitting the ground. When considering this problem ignore air resistance.

Answer 1

$$PE=KE,$$ $$mgh=\dfrac{1}{2}mv^2,$$ $$v=\sqrt{2gh}=\sqrt{2\cdot9.8\ \dfrac{m}{s^2}\cdot100\ m}=44.27\ \dfrac{m}{s}.$$