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Need help on how current flow works.

  1. Jun 4, 2014 #1
    Hi, I didn't know if this is a homework question it didn't fit any of the template layout. If it is let me know and I'll post it there but I have some question that have become very frustrating and more frustrating in finding answers to them. If you are able to answer this question you just helped a student out and I thank you. The question is "At the negative terminal of a battery does the electrons of the net negative charge atom flow through the copper wires to the cathode end or is it only the copper atoms valence electrons that flow to the positive terminal of the battery or does both happen? and the electrons in the battery only fill in the copper atom holes?" Another one that puzzles me is does the net negative charge battery atoms ever strike the copper atoms valence electrons? And if so is that what causes heat? or is heat produced when the copper atoms strike each other when they randomly zigzag to the positive end of the terminal? What happens to the electrons that is received at the positive end of the battery does the electrolytes transfer the electrons to the negative terminal so that it can repeat the flow again? Last one when the copper atoms loose electrons because it's attracted to the positively charged terminal. That copper atom becomes a cation how does current flow if that atom has a net positive charge? Once again i really appreciate any input that you give me as it has perplexed me for sometime.
    Last edited: Jun 4, 2014
  2. jcsd
  3. Jun 4, 2014 #2
    What are "net negative charge battery atoms"?
    Can you really explain what those words strung together actually mean as an ensemble?

    Voltaic cells function as a result of what is called half-cell reactions.
    A battery is several voltaic cells connected together, so technically that is why you have a 1.5v dry cell for your electronic equipment and a 12 volt battery for your car.
    Holes are not a significant charge carrier for a battery.

    The chemical reaction with the voltaic cell give one terminal a positive charge and the other a negative charge. Completing a circuit between the terminals allows electrons to flow from one terminal to the other. Within the cell itself there is an an electrolyte, composed of anions (negative ions ) and cations (positive ions ). The anions give up an electron at the anode and the cations accept an electron at the cathode.

    A zinc-carbon dry cell
    Last edited: Jun 4, 2014
  4. Jun 4, 2014 #3
    Thank you for your reply :D. I wasn't expecting one so quick. When I say net negative charge battery atoms. I mean the negative terminal of the battery has gained electrons when circuit is closed and the atom becomes an anion. Isn't that how pressure occurs in the negative end of the battery? The force of repulsion because of electrostatic builds up pressure and that pressure is voltage? The other question was if the electron of the battery and copper valence electrons flow to the positive end of the terminal or is it just the copper atom valence electrons that flow to the positive end of the battery? and does the electrons in the battery strike the copper atom valence electrons?
  5. Jun 4, 2014 #4


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    This is incorrect. The negative terminal of the battery is at a negative voltage and electrons move away from it towards the positive terminal. Voltage is generated by chemical reactions between the electrolyte and the electrodes that cause the products of the reaction to gain or lose electrons, generating a voltage.

    Electrons are given up by the reaction on one electrode (the anode), and are taken in by the reaction on the other electrode (the cathode), so the current consists of electrons from the battery and the copper.

    See the following links:

    http://en.wikipedia.org/wiki/Battery_(electricity [Broken])
    Last edited by a moderator: May 6, 2017
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