1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Induction - in two parallel wires - affecting voltage?

  1. Jul 7, 2015 #1
    Hypothetical, Two parallel wires, wire 1 and wire 2. Trying to understand my system.
    A) Wire 1 has a constant current which is being driven by a V and power supply.
    Is there a current in wire 2 if the current in Wire 1 is constant?

    B) Wires A and B both have current flowing through them. Does the magnitude of the current in 2 depend on the current in 1?

    C)Does the voltage drop over wire 2 change depending on the steady state magnitude of current in wire 1?
  2. jcsd
  3. Jul 7, 2015 #2


    User Avatar
    Staff Emeritus
    Science Advisor

    No. Without an alternating current there is no changing magnetic field and hence no induction.

    It does not.

  4. Jul 8, 2015 #3
    First, understand that the dependence of the current in wire 2 could be dependent upon only changes in the current of the wire 1 with a few odd exceptions. The current in wire 2 could be completely independent of that in wire 1 if wire 2 is driven by a constant current source.

    In general, this is not a simple question, if say, the resistance of wire 2 is dependent upon an applied magnetic field due to wire 1. I will treat it as a simple.

    To answer, I'll assume that wire 2 is a closed loop without a driving voltage or current source unless implied otherwise.

    no, the constant current wire 1 generates no changing magnetic field to effect the electric current in wire 2.

    no. the current flowing in wire 2 does not depend on the current in wire 1, but how much the current in wire 1 changes over time. The current in wire 2 certainly depends on how much the current in wire 1 changes.

    nope, and it seems Drakkith and I agree on all points.
    Last edited: Jul 8, 2015
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook