Orbits of the Moon and Earth and Extensions
In Case You Have Forgotten -- Data:
The earth to moon distance is about 240,000 miles and the moon takes about one month to
orbit the earth.
The earth is about 93 million miles from the sun and takes one year to orbit the sun.
Estimate how fast is the earth moving around the sun?
Something to Do [STD]:
Estimate how fast is the moon moving around the earth?
Make a drawing of how you think the moon moves around the sun.
Compare your diagram with Partners Instructors Classmates (PICs).
Check this with the PhET simulation at
http://phet.colorado.edu/en/simulation/gravity-and-orbits
[The Note to Teachers (TNT): In the above the activity is asking the participant to make a prediction
(drawing) based on numerical evidence. If the participant is not engaged, they may not realize that the
results of the first two questions determine how the diagram will look. The interesting about this
exercise is that few books or other resources discuss this particular aspect of planetary motion so it is
not as likely that the participant will start the task with a preconceived notion.]
The time it takes (sometimes called the period) for the earth to orbit the sun depends on several factors.
What do you suppose would be of importance to determine the period of the earth’s orbit about the
sun?
Design an experiment with the PhET simulation to test if these parameters are important.
[TNT: The redesign of the AP Physics B – into AP Physics 1 & 2 == will include tasks such as this – design
an experiment. By the way, many of the same people who worked on the NGSS also worked on the AP
redesign.]
Apply your experimental design to see if your parameters are indeed important to the orbit of the earth
about the sun. By extension, do you think the parameters are important for all orbiting bodies?
Your response to the last discussion can be tested with the PhET simulation “My Solar System” at:
http://phet.colorado.edu/en/simulation/my-solar-system