Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Does accelerating electrons give a higher voltage

  1. Sep 24, 2011 #1
    the way im understanding how voltage works is how fast one coulomb is passing a point. so if i push more electrons passed a point, it actually gives it a higher voltage?
    that and, if i have a screen with a positive potential across it and an electron stream flowing towards it, would the stream accelerate up to the voltage?
    ps, im pretty sure the term electron volts is going to be said, im too tired to think and just regurgitated hours of trying to understand this.
    goodnite
     
  2. jcsd
  3. Sep 24, 2011 #2
    Seems like you may have voltage and current mixed up...it's difficult to tell from your phrasing. That's common when starting out studying electricity.

    One way to think about it is via the old analogy: think of water molecules as "electrons" flowing and water pressure as voltage. A coulomb is analogous to a quantity of water (molecules)...say a quart or a liter (and a coulomb is q =it). So if you have more water (molecules) passing a point, you have more CURRENT (molecules) flowing. That can be accomplished by increasing the size of the pipe, like decreasing resistance, for example, or by increasing the pressure (voltage).

    To push more electrons past a point, given a fixed circuit resistance, yes you'd have to increase voltage...that's the only way to get more current flowing.

    It's typically convenient to think of voltage as causing the motion of electrons in a circuit....typically they won't move much by themselves except locally as in their local electron cloud. Some voltage (energy) needs to be applied to break them losse from their local attraction to a positively charged nucleus.


    An electron volt is the amount of kinetic energy gained by an electron when it accelerates through an electric potential difference of one volt. So given enough time and distance, an electron might reach the full KE available from the local voltage potential...or it might strike the positive grid potential before it reaches that energy level.
     
    Last edited: Sep 24, 2011
  4. Sep 25, 2011 #3
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook