From the time of Aristotle (384-322 BC) until the late 1500’s,
gravity was believed to act differently on different objects. -
Drop a metal bar and a feather at the same time… which one hits
the ground first? - Obviously, common sense will tell you that
the bar will hit first, while the feather slowly flutters to the
ground. - In Aristotle’s view, this was because the bar was
being pulled harder (and faster) by gravity because of its
physical properties. - Because everyone sees this when they drop
different objects, it wasn’t questioned for almost 2000 years.
Galileo Galilei was the first major scientist to refute (prove
wrong) Aristotle’s theories. - In his famous (at least to
Physicists!) experiment, Galileo went to the top of the leaning
tower of Pisa and dropped a wooden ball and a lead ball, both
the same size, but different masses. - They both hit the ground
at the same time, even though Aristotle would say that the
heavier metal ball should hit first. - Galileo had shown that
the different rates at whi