Preflight assignment 5


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  1. Taylor (on p. 91) argues that rxF =0 for the case of a planet orbiting the sun. He then uses that to claim that the planet's orbit "is confined to a single plane containing the sun", and the problem of orbits is thus 2-D, not 3-D. Explain in your own words how you draw that conclusion from "rxF=0".


  2. If you take your origin as the center of the galaxy (rather than the center of our solar system), is rxF still zero for the case of a planet orbiting the sun? -- If you answer "yes", please explain carefully why this is so. (Be sure to read the paragraph after Taylor 3.14 and refer to it)
    -- If instead you answered "no", I'd like you to reconsider the question above. Since you are claiming torque is NOT zero, does that mean that your argument in question 1 is flawed? As viewed from the center of the galaxy, does that mean the earth's orbit is NOT confined to a single plane containing the sun?




  3. This is exam week. What topic(s) have we covered that you feel the shakiest on, (and can you articulate what the difficulty you're having is?)




  4. Exams don't stop the class! Tuesday's reading is Taylor 4.1-4.2. Please submit a question you have about the reading assigned for the upcoming class. What seemed hard, was something confusing, what would you like us to spend class time on? If you can't come up with any question, how about a comment - (did anything strike you as interesting? )
    Reminder: the reading assignments are always on our course calendar


    Thanks for your time.

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