# [Answer] What did Galileo discover in his legendary experiment on the Leaning Tower of Pisa?

###### Answer: Galileo found that a heavier stone does not fall significantly faster than a lighter one.
What did Galileo discover in his legendary experiment on the Leaning Tower of Pisa?

Between 1589 and 1592 the Italian scientist Galileo Galilei (then professor of mathematics at the University of Pisa) is said to have dropped two spheres of different masses from the Leaning Tower of Pisa to demonstrate that their time of descent was independent of their mass according to a biography by Galileo’s pupil Vincenzo Viviani composed in 1654 and published in 1717. Accordi…

Between 1589 and 1592 the Italian scientist Galileo Galilei (then professor of mathematics at the University of Pisa) is said to have dropped two spheres of different masses from the Leaning Tower of Pisa to demonstrate that their time of descent was independent of their mass according to a biography by Galileo’s pupil Vincenzo Viviani composed in 1654 and published in 1717. According to the story Galileo discovered through this experiment that the objects fell with the same acceleration proving his prediction true while at the same time disproving Aristotle’s theory of gravity (which states that objects fall at speed proportional to their mass). Most historians consider it to have been a thought experiment rather than a physical test.

At the time when Viviani asserts that the experiment took place Galileo had not yet formulated the final version of his law of falling bodies . He had however formulated an earlier version which predicted that bodies of the same material falling through the same medium would fall at the same speed. This was contrary to what Aristotle had taught: that heavy objects fall faster than the lighter ones and in …

At the time when Viviani asserts that the experiment took place Galileo had not yet formulated the final version of his law of falling bodies . He had however formulated an earlier version which predicted that bodies of the same material falling through the same medium would fall at the same speed. This was contrary to what Aristotle had taught: that heavy objects fall faster than the lighter ones and in direct proportion to their weight. While this story has been retold in popular accounts there is no account by Galileo himself of such an experiment and it is accepted by most historians that it was a thought experiment which did actually take place. An exception is Stillman Drake who argues that it took place more or less as Viviani described it as a demonstration for students. Galileo set out his ideas about falling people and about projectiles in general in his book Two New Sciences . The two sciences were the science of motion which became the foundation-stone of physics and the science of materials and construction an important contribution to engineering. Galileo arrived at his hypothesis by a famous thought experiment outlined in his book On Motion . This experiment runs as follows: Imagine two objects one light and one heavier than the other one are connected to each other by a string. Drop this system of objects from the top of a tower. If we assume heavier objects do indeed fall faster than lighter ones (and conversely lighter objects fall slower) the string will soon pull taut as the lighter object retards the fall of the heavier object. But the system considered as a whole is heavier than the heavy object alone and therefore should fall faster. This contradiction leads one to conclude the assumption is …