Kepler ’s Laws
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By gilroy0 |
| on February 23rd, 2009 | |
This assignment is meant to be done on Tue Feb 24 while Mr. Gilroy is at the Blood Drive, but you can complete it at a different time if you want. The written part is to be handed in on Thu Feb 26. You will be asked to run some online simulations and answer questions. Please type your responses (you don’t need to type the question), print it out, and hand it in on Thursday.
You should feel free to work together on these but be sure to write your answer in your own words. You should also feel free to utilize the Internet as a resource but again, translate what you find into your own words. In either case, be sure to give credit where it is due!
Run the Kepler’s Law simulation at UNL (http://astro.unl.edu/naap/pos/animations/kepler.swf). NB: You probably want to do this in another tab or window so that you can switch back to these directions.
The “semi-major axis” is essentially what we mean when we say “the distance from the Sun”.
1. Ready the simulation for First Law by making it look like the following (click to enlarge).
2. Play with the slider marked “eccentricity” and see what happens to the orbit.
Q01: What is the effect of increasing the eccentricity? What happens when eccentricity is set to 0?
3. Set up the simulation for 2nd Law by clicking “Kepler’s 2nd Law” on the tabs in the lower left and then make the parameters the same as the following:
4. Press “start animation”. Then press the “start sweeping” button. This will color in a region whose area is 1/16 of the total orbit. (You can change that number.)
Q02: What can be said about the speed of a planet when it is close to the Sun, as opposed to when it is far away? (That is, which is faster.)
Q03: Does your answer depend on the semimajor axis? Does it depend on the eccentricity?
For the next two questions, you will have to look out on the Net. Be sure to give your source.
Q04: What doe the words “aphelion” and “perihelion” mean? What is the root of these words?
Q05: List the planets in order of eccentricity, from least eccentric to most. (The planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.) Where would Pluto fall in this list?
