You should understand the words and concepts listed here:

• orbit
• eclipse (total, partial, annular)
• ellipse
• (semi-) major axis
• (semi-) minor axis
• eccentricity
• geocentric
• heliocentric
• retrograde (motion)

Also, various concepts associated with newton's laws of motion and Newton's law of gravity:

• mass
• velocity
• acceleration
• center of mass
• gravity
• Newton's law of gravity
• (Newton's) gravitational constant G
• Newton's laws of motion
• action and reaction (Newton's third law)

This is a shorter than the list for the first chapter, but still grouped into clusters.

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The URL for this page is http://www.atsweb.neu.edu/physics/m.vaughn/PHYU111_F07/vocabulary_1.html
posted 14 September 2007, revised 20 September 2007