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Homework Help: Speed of light question?

  1. May 24, 2005 #1
    I've got a question I'm working on:

    A communications satellite is in an orbit that is 3.2 X 10^7 m directly above the equator. Consider the moment when the satellite is located midway between Quito, Equador, and Belem, Brazil; two cities almost on the equator that are separated by a distance of 3.7 X 10^6 m. Find the time it takes for a telephone call to go by the way of satellite between these cities. Ignore the curvature of the earth.

    -- eek! I'm not sure where to start! Is this related to the speed of light in any way?

    thanks for the help!
  2. jcsd
  3. May 24, 2005 #2


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    Yes, this involves the speed of light, but the main work is geometry of right triangles. Draw a picture that shows the relationship described, compute the lengths involved and proceed from there.
  4. May 24, 2005 #3
    All electromagnetic waves travel at the speed of light, I'm assuming theyre talking abuot a geosynchronous orbit where the satelite is in a fixed position.
  5. May 24, 2005 #4
    thanks-- all i need to to was draw a picture :)

    thanks again
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