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Homework Help: Discharged electrodes and charges: electric slingshot

  1. Mar 23, 2010 #1
    1. The problem statement, all variables and given/known data
    working on feasability of a new satellite launcher that will save rocket fue. the design of the launcher is an electric slingshot. the launcher consists of 4 electrodes arranged in a horizontal square with sides 5 m long. the square of electrodes is mounted so that the center square is 15 m directly above the satellite that is to be launched. a power supply placers +32 C of charge on each electrode and -128 C of charge on the satellite. when the satellite is released, it launches straight up and passes through the center of the square. just as the satellite is passing through the square, the electrodes are discharged. the satellite then continues to move upward under only the influence of gravity. is this launcher sufficient to launch a 100 kg satellite above earth's atmosphere? the height of the atmosphere is about 10 km.

    2. Relevant equations

    plz c attached

    3. The attempt at a solution

    plz c attached

    Attached Files:

    • crp.pdf
      File size:
      454.4 KB
  2. jcsd
  3. Mar 23, 2010 #2


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    The way I interpret the problem statement, the electrodes are thin rods. Put four of these electrodes together (arranged horizontally) and you end up with a horizontal square.

    In your attachment, you have each of the electrodes being a square, such that when all brought together they form a cube. I think the problem might be a little easier if you treat the electrodes as line charges forming a square (instead of a cube).
  4. Mar 23, 2010 #3
    i reworked it, per your suggestion, and am getting stuck with trying to see if the voltage potential difference offers enough energy to get the rocket over the giant pull of the earth's gravity. plz c attached. thx very much for your help. i really appreciate it.

    Attached Files:

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