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Currents - Electricity

  1. Sep 16, 2003 #1
    At my school we are currently investigating Currents & Electricity and me and my teacher would like to know why Current was giving the symbol 'I' instead of say 'C' more so when Volts is given 'V' and Amps is giving 'A'.

    Both of us would really like someone to shead some light onto this matter.
  2. jcsd
  3. Sep 17, 2003 #2
    does anyone acutally know...

    i was talking to my teacher again and we have started thinking it is latin like AU being Gold in the periodic table
  4. Sep 17, 2003 #3


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    Staff Emeritus

    "Why is current designated "I"? The usage goes back to 1827 formulation of Ohm's law. Ohm found that the "intensity" of a current through a load is directly proportional to the emf of source driving the current."

    Source: http://www.ieee.org/organizations/history_center/faqs.html# [Broken]"I"

    Also as a note: C stands for Coulombs.
    Last edited by a moderator: May 1, 2017
  5. Sep 18, 2003 #4


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    Amps and current are the same thing.

    It is proper to state as follows:

    E = 10V
    I = 10A

    E and I are the symbols, but V and A are the labels.

    Could also be stated:

    "The voltage equals 10 volts."
    "The current equals 10 amperes."

    Concerning resistance:

    R (resistance) = 1 <Omega symbol> (can't figure out how to make it)
  6. Sep 18, 2003 #5
    The capital letter "I" came from the word "intensite" (missing an accent over the last "e"). It is the French word for current.
  7. Sep 19, 2003 #6
    Re: Re: Currents - Electricity

    Amps and Current is not the same thing.

    Amps is the measure of current

    Like miles is a measure for length

    Anyway the other two posts helped with my question. So thanks a lot dduardo & BoulderHead
  8. Sep 19, 2003 #7


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    Re: Re: Re: Currents - Electricity

    Isn't that more of less what I stated when I said that: "E and I are the symbols, but V and A are the labels." ?????????????

    The way you first stated it it made it sound like they were 2 totally different properties of electricity.

    The definition of an ampere is x number of electrons going past a point in one second. The ampere is a rate that can be compared to gallons per minute in a pipe. The definition of current would be the movement of matter (water for instance in a river) down a medium. In the case of electricity, it would be electrons moving down a conductor.

    So you're split'n hairs. It is proper to say: "The maximum current allowed before the conductor melts is 5 amperes." It is also proper to say: "The maximum amperage allowed before the conductor melts is 5 amperes."

    Hey if YOU'RE gonna get technical on me, then well what can I say?

    Don't bother thanking me for my post, you didn't on the last one.
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