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!

Homework Help: Capacitors Charging Linearly

  1. Mar 16, 2010 #1
    1. The problem statement, all variables and given/known data
    When a does a capacitor increase in charge linearly?


    2. Relevant equations
    C=Q/V


    3. The attempt at a solution
    If I am correct, it is when the capacitor is being directly charged by a battery. When there is a resistor, we get an RC circuit scenario where capacitor charges exponentially.
     
  2. jcsd
  3. Mar 16, 2010 #2

    Jmf

    User Avatar

    Linearly with respect to what? time? Can V change too?

    If an ideal resistor were charged with an ideal (no internal resistance) battery, the plot of charge against time would not be linear but would look like a step, from what I understand.

    But of course in practice this is impossible, since there will always be some measure of resistance in the circuit. Does this help clear things up?

    Here's an interesting question: If V were to change over time, how would the plot of V against time look if the plot of Q against time was linear? (I think maybe this was what you were meant to work out).
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook