1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    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!

Voltage drop across resistors

  1. Mar 27, 2013 #1

    I am having conceptual difficulties trying to understand how voltage is dropped across a resistor. The whole idea of it is confusing to me, where does this voltage go?

    Could it be explained in terms of point charges and electric fields, which is how I am able to visualize potential difference.

    The way I see it, the positive charges move across a resistor and face some sort of resistance to their motion, but how does that relate to the charges losing potential?
  2. jcsd
  3. Mar 28, 2013 #2


    User Avatar
    2017 Award

    Staff: Mentor

    Voltage is not a material, it does not "go" somewhere.
    Where does the height of a ladder (not your height!) "go" if you climb it down?

    They need some energy to cross the resistor. Moving positive charges are quite rare.
  4. Mar 28, 2013 #3


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Think of it in terms of power.

    Power = I ΔV.

    It escapes as heat.
  5. Mar 28, 2013 #4
    positive charges don't move as much as the electrons move to fill "electron holes"
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook