ISP 205, Section 3 (Stein & Hufnagel) Spring 1997
Motion Activity
30 January or 4 February 

                                      Name: __________________________


                                      Student Number: ________________
You will not be graded on the accuracy of your predictions, only their completeness. You will be graded on the accuracy of your observations. We suggest that you use a pencil, at least for the "Motion Observations" section, so that you may change your answer if you wish.

Motion Predictions

Go ahead and complete these two "Motion Prediction" diagrams now. Please work alone for this section.

1. On the diagram below, representing the Earth and the Moon, sketch your prediction for the path the Moon would move along if its orbital motion were slowed, but not halted.

Sketch predicted motion of Moon
2. On the diagram below, again let the large sphere represent the Earth and the small sphere represent the Moon. The Earth and the Moon attract each other by the force of gravity. Sketch your prediction for the path the Moon would move along if its orbital motion were stopped.

Sketch predicted motion of Moon

Motion Observations

Your instructor will show you a series of computer simulations of the Moon falling toward the Earth with different velocities. She will repeat the simulation as many times as you need. Feel free to ask questions. For right now, work alone.

1. On the diagram below, representing the Earth and the Moon, sketch your observation of the path the Moon did move along when its orbital motion was slow.

Sketch observed motion of Moon
2. On the diagram below, representing the Earth and the Moon, sketch your observation of the path the Moon did move along when its orbital motion was stopped.

Sketch observed motion of Moon
When everyone is done looking at the simulations, you may compare your "Observation" sketches to your neighbor. Change them if you wish. Think about how your observations agree or disagree with your predictions, but please do not change your predictions. (Remember, you aren't graded on the predictions.) Hand in your paper for credit.
Visions of the Universe
Bob Stein's home page, email: stein@pa.msu.edu