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Flow of current

  1. Jun 1, 2013 #1
    If potential difference between two points of wire is very low(as potential drop is very low due to low resistance) then how can there be flow of current in the wire?
    Last edited: Jun 1, 2013
  2. jcsd
  3. Jun 1, 2013 #2


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    Staff: Mentor

    Ohm's Law: current = V/R

    When V is very small, if R is very small, too, then current can be large,

    e.g., 0.001 volts/0.0001 Ohms = 10 amps
  4. Jun 1, 2013 #3
    Because it's low but not zero.
  5. Jun 3, 2013 #4
    Why do you expect no current in the circuit? any reasons?(pardon my rudeness if any)
    First of all ,you have to understand what parameters we can control and what we cannot ,assuming a normal dc voltage source (a battery),and a given resistance wire.

    ->Now you can choose the voltage by choosing your own battery.
    ->You can choose the resistance by choosing the length ,area and the material of the wire(an engineering issue).
    ->The current gets fixed as a consequence of Ohm's law.(V/R=I)
    let's say the voltage and the resistance you have chosen are some NON-ZERO values.
    V/R = I ≠ 0
    There is a non-zero current.
    PS:i think you came up with this question by considering two points on a conducting wire.
    But i think this explanation will serve the purpose.
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