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How many kilowatts does a light have?

  1. Dec 12, 2003 #1
    i want to know how many kilowatts does a light have? & i want to know who invented lightning conductor?

    please answer it sooooooon!
    or email it to:



  2. jcsd
  3. Dec 12, 2003 #2
    Your first question is very poorly worded. What exactly do you mean? If you mean an electric light, look at the bulb and it will tell you. My lamp at the side of me now is 60W ie 0.060kW.

    regards lightning conductor - do a search on Google.
  4. Dec 12, 2003 #3


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    Staff Emeritus
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    Lamps can have just about any power ratings -- the power dissipated by the lamp depends upon its resistance and the voltage applied to it. Flashlight bulbs and search lights are very different in their power ratings.

    - Warren
  5. Dec 12, 2003 #4


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    Staff: Mentor

    Compact flourescent light bulbs generally consume about 10-20W at about 5x the efficiency of an incadescent. Regular incadescents come in 40-100w versions. Though like chroot said, light bulbs come in all sizes - down to a few miliwatts and up to a few thousand watts.

    For the second part, do a google search for Thomas Edison.
  6. Dec 12, 2003 #5
    Ben Franklin invented the Lightning Rod, or Lightning Conductor in 1752.
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