Physics

concept reinforcement quiz 6

The purpose of this page is to help you understand basic astronomy and develop related skills.  Be prepared to answer or do all the following:

Section 1: Development of the theory:

• What was Eudoxos's motivation for developing his system of homocentric spheres?
  
  
• How did Eudoxos explain the motions of the stars and the normal and retrograde motions of the planets?
  
  
• Explain the contributions of Aristarchos and Eratosthese.
  
  
• Using a diagram, explain how Claude Ptolemy explained the retrograde motions of the planets.   How did he explain the seasons?
  
  
• What was the main advantage of Ptolemy's theory of the heavens over Eudoxos's homocentric spheres?
  
  
• Our civilization has been built on the same assumptions about of observation, measurement, and logic formulated by the Greeks.   Trace the historical path that these assumptions took through several cultures from their origin to us.
  
  
• Characterize the middle ages in Europe (also known as the dark ages) in terms of the goals of the people and their attitudes towards science, technology, and other worldly pursuits.
  
  
• Describe how European standards of living changed during the middle ages due to the shift in their attitudes towards technology and science.
  
  
• Characterize how Europeans' attitudes towards science changed between 1000 AD and 1400.
  
  
• What was Niclolas Copernicus's primarily objected to Ptolemy's explanation of planetary motions?
  
  
• How did Copernicus explain the westward motion of the sky?   How did he explain the seasons?
  
  
• Using a diagram, explain how did Copernicus understood retrograde motions of the planets.
  
  
• Was Copernicus unaware of old ideals, a revolutionary, a renaissance man, or a true scientist who favored the theory which had the most evidence?
  
  
• Which assumptions were made by both Copernicus and Ptolemy?   What assumptions were made by only Ptolemy?   ...by only Copernicus?
  
  
• At the time, what was the main advantage of Nicholas Copernicus' planetary system over Ptolemy's theory?
  
  
• Compare the simplicity of the Copernicus' system of the sky with that of Ptolemy.
  
  
• Why did most of Copernicus' contemporaries rejected his theory?
  
  
• The lack of stellar parallax was evidence that the earth did not move about the sky.   But if astronomers someday find stellar parallax, how could Ptolemy's theory be modified to account for the parallax?
  
  
• How did Copernicus encourage belief in extra terrestrial life?
  
  
• Some people believe the Greeks started science.   Others say the Egyptians and Babylonians started science.   What is your definition of science?   Using your definition and historical examples, explain who really should get the credit for starting science?
  
  
• Why study Greek science?

Section 2: Mathematical section: Apply your understanding by making specific predictions.  List all equations you use, and show substitutions and algebra.   Show your stepwise solution procedure.  Answers need to be reported with the correct uncertainty (i.e., the correct number of significant figures), and appropriate unit labels:

• Eratosthenes knew that at the summer solstice, sunlight shown straight down the town well at Cyrene.   In Alexandria, 930 kilometers to the north, Eratosthenes measured at noon on the day of the summer solstice that the sun was 1/50 of a circle away from being directly overhead.   Using a diagram, show how Eratosthenes used this information to find the circumference of the earth.