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Tycho Brahe. |
The concepts involved in circular motion stemmed
from the observations of the Danish philosopher Tycho Brahe (1546-1601). Brahe
made his observations from an island in the sound between Denmark and Sweden, called
Hveen. In particular, Brahe compiled extensive data on the planet Mars, which would later
prove crucial to Kepler in his formulation of the laws of planetary motion because it
would be sufficiently precise to demonstrate that the orbit of Mars was not a circle but
an ellipse. |
Johannes Kepler.
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Brahe's assistant, Johannes Kepler
(1571-1630), furthered the study of circular motion. By basing his work on Brahe's
research, he concluded that the following laws were true:
- The path of each planet around the sun is an ellipse, with the sun at one focus.
- Each planet moves so that an imaginary line drawn from the Sun to the planet sweeps out
equal areas of space in equal periods of time.
- The cube of a planet's average distance from the sun divided by the square of it's
period is a constant for all planets.
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Sir Isaac Newton.
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Over fifty years after Kepler had stated his
laws, Sir Isaac Newton was able to prove them mathematically using his law of universal
gravitation. Newton's law of gravitation can be explained by this diagram: 
The force on either mass (Fg) can be expressed by the equation:
Fg = (Gm1m2)/(d2)
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What force affects this hurricane?
Who formulated the theories and laws
of circular motion?
What type of motion does this
heavenly body exhibit with respect to the Earth?
Send e-mail to: tbone_tabor@hotmail.com
with questions and comments. |
