Homework to submit next class

1.  Briefly discuss each of Kepler's 3 laws.

2.  At what point in its orbit is the Earth closest to the Sun?

3.  What causes seasons?

4.  What is a semi-major axis of orbit (a)?

5.  What is an Astronomical Unit (AU)?

6.  An object is released from rest and falls without air resistance.
     a.  How fast is it moving after 3 seconds?
     b.  How far will it have fallen in this time?


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