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Charges on Faraday ice bucket like conductors

  1. Feb 21, 2008 #1

    I have problems with charge distributions of buckets and other conductors which has a cavity. If there is experiments, photos, detailed examples about this kind of charges then glad to learn the links in net.

    Suppose have a conductor like Faraday ice bucket. And tied two un-charged electroscopes via switchs to inner and outer surfaces of bucket. Can we say that both electroscopes loaded the same charge everytime?

    More detailed;

    1. first bucket loaded then both switch closed (what about in opposite order?)

    2. a positive charge hanged down till the mid of bucket switchs(before - later) closed

    3. a positive charge make charge to inner wall. Switchs(before - later) closed

    4. Grounded from inner/outer faces while a positive charge hanged to inwards and switchs closed.

    5. If a charged conducter sphere has a pit what about the charge distribution? Is there charge in pit? Much or less then curved surface? The same thing as pointed surfaces?

    I was guess the electroscopes must have the same charge as the charge of tied surface. But suppose this is not true. Sorry asked lot but I am confuced.

    Thank you
  2. jcsd
  3. Feb 23, 2008 #2
    I want to add a picture to my question. And i suppose must say "Faraday's ice-pail experiment" :) I am afraid can not explain all my idea with my poor English. So avoid to write complex sentences. Beside, prefer to ask my questions.

    * As i know the charges on a conducter must be outside of surface. But somewhere a sentence I read that, "pits over a conductor is like the points". If this true, the pit must has much charge. But as we know from "Faraday's ice-pail experiment", inside has no charges. All of them are over the outer surface. Is really pits like points?

    * In "Faraday's ice-pail experiment", connected the outer surface of an insulated metal pail to an electroscope by means of a conducting wire. He then lowered a positively charged ball into the pail, supporting it by a silk thread and electroscope charged by induction positively. The, leaves remainded apart without change when the ball was allowed to contact the inside of the pail.; the charges on the ball was therefore lost. After the ball was removed, it was evident that the outside of the pail(and the electroscope) had acquired all the charge originally placed on the ball.

    what would be the charge of electroscope if he also connected another electroscope to the inner surface? I suppose, other electroscope charged with;

    Before the ball contacted: negative
    After the ball contacted: any charge

    What is the truth?

    Attached Files:

    Last edited: Feb 23, 2008
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