The Development and Impact of The Law of Falling Bodies

1. The Development and Impact of The Law of Falling Bodies Xu Yan WeimoXu TaoranXue

2. Introduction • Among the 100 Greatest Discoveries chosen by the Science Channel’s, The Law of Falling Bodies set down by the well-known physicist Galileo Galilei stands on the top of the list. This noble discovery outweighs the other ones not only on the impact upon society but also on the hardship and disregard the discovery met during the process.

3. Before the discovery, the whole society held the generally accepted belief raised by Aristotle, the most powerful authority at the time in 1600s, that how a body falls depends on its weight and heavy objects fall faster than lighter ones. Aristotle held the opinion that All objects under the moon desired to be in their natural place. He stated that Lighter objects tend to have less 'earth,' which attract less gravity than the heavier objects which attract more gravity (White), and that’s why a one handred pound ball should definitely fall faster than a one pound ball. However, Galileo looked deeply inside and found that Aristotle’s assumption were inconsistant with the real world.

4. According to Galileo, in the same vacuum, all objects with unequal weights would fall with the exactly same speed. He also pointed out that the motion of an object would remain unchanged unless an external force acted on it. Galileo’s assumption was contradicted to Aristotle’s idea and to what we saw in our daily life.

5. In Galileo’s theory, it is the air resistance and friction that causes heavy rocks fall faster than light rocks. However, no one listened to Galileo. As we all knew, Galileo then did a famous experiment. He dropped two balls, which were different in mass, from the leaning tower of Pisa. Then, as what he predicted, the two balls with different mass hit the ground at the same time. Unfortunately, the experiment is not proven to be a real one. Instead, most physicists and scientists consider it as a mental experiment which has never been conducted in the real world because there is no accurate description and records about this experiment in the history.

6. In addition, many scientists claimed that this experiment required very accurate measurements of mass, time, length, which appeared to be impossible with the technology of 1600.(Roben) However, Galileo finally won the tug of war. His theory of the Falling bodies is proven by many famous and prominent scientists such as Newton. He accepted Galileo’s theory and used it in his own discovery of Gravitation. Galileo’s law of falling bodies built a foundation for further development in physics. In addition, Galileo’s experiences and instances gave many other scientists a lesson and inspired them to explore the world with an open mind.

7. References • Rubin, Julian. "Galileo Galilei. The Falling Bodies Experiment." • Following the Paths of Discovery. November 2009. Web. 10 Feb. 2011. • <http://www.juliantrubin.com/bigten/galileofallingbodies.html >. • White, Michael. "Gravity: From Cave-men To Newton." science20. N.p., 3 Feb. • 2010. Web. 10 Feb. 2011. • <http://www.science20.com/adaptive_complexity/gravity_cavemen_newton>.