Question

Suppose Galileo dropped a lead ball (100 kilograms) and a glass ball (1 kilogram) from the Leaning Tower of Pisa. Which one hit the ground first? (Assume that there is no air resistance.)

Answer 1

Use F=ma
and the force under gravity
=mg

FOR BOTH balls ma=mg

Work out the acceleration of each - and see what you come up with - it may surprise you, but this is a true fact of physics