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Insulating sphere

  1. Sep 15, 2009 #1
    I can't quite understand why this occurs. When a person is standing on insulating stool, and holds a large metallic sphere, which is charged with generator, why is it safe for him to do this?

    Why is it unsafe for another person to touch the sphere after it has been charged?

    My guess is that the person standing on the stool is safe because the charge is contained in the sphere because it cannot pass through him to the ground (because of the insulating stool).

    However, charge can pass through the person standing on the ground because he is a conductor.

    My question is, would it still be unsafe if the other person stood on an insulating stool and then touched the charged sphere?
     
  2. jcsd
  3. Sep 16, 2009 #2
    It's safe for a person to hold a negatively charged sphere as long as the person holding it is insulated from ground (if he weren't, the charge would flow through him into the ground).

    It is safe for any number of people to feel on the sphere as long as they are all insulated. If one person touches the sphere and their toes are dug into the ground all the negative charge will flow right through their chest and into the ground, which can be bad.

    (Remember, 'ground' usually means dirt. If you are standing on the floor of a building I would think you would be insulated, and if you have shoes on I would think you would be insulated as well (even when standing on dirt). The dirt is positive because electrical generators are built to do this (I think).)

    (Disclaimer, I don't know what I'm talking about... So don't blame me when you get shocked into cardiac arrest because I said you would be safe)
     
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