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Homework Help: Very tough Question

  1. Dec 5, 2005 #1
    Very tough Question !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    Ok so ... My teacher has given us a problem to solve for bonus marks and it is a really tough question. I also really need these bonus marks if i want to get anywhere =]. Anyways here is the question

    Astrologists believe that the planets in our solar system influence the lives of people here on earth via their gravitational forces. Your task is to debunk this myth. Consider an average human being with an average mass (say 60kg) Calculate the maximum gravitational force exerted on this average person by all of the planets in the solar system (other than earth of course ((*reminder to myself that the sun is not a planet))). Use the data on page 271 of your textbook for your calculation

    Ok. How would i go on about solving this equation, what things must i know and what diagrams must i draw.
  2. jcsd
  3. Dec 5, 2005 #2
    You must know the distances of orbits of all planets from earth. take a point in the orbit of every planet such that it isclosest to earth. you must know, what is the distance from centre of these planets at that point. itheink you got somewhata picture. now work out
  4. Dec 5, 2005 #3


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    Homework Helper

    Use the equation for Newton's law of gravitation. Plug in the values of mass from your tables with 60kg as the person's mass. You can assume the closest possible distance to the Earth of each planet (i.e. suppose the planets were all aligned, then distance from Earth to Mars would be radius of orbit of Mars subtract radius of orbit of Earth).

    You should then be able to find the gravitational force of each planet acting on a 60kg human. What order do you expect this number to be?
  5. Dec 5, 2005 #4
    merci mezarashi joon, damet garm
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