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!

Very basic circuits 1 question. Charge and current

  1. Oct 2, 2014 #1
    1. The problem statement, all variables and given/known data
    Find the charge q(t) flowing through a device if the current is: 20 cos(10t + π/6)μA, q(0) = 2 μC

    2. Relevant equations
    ∫ i(t)dt +q(0)

    3. The attempt at a solution
    I am studying for a test by working all the problems I can and then looking at the solutions manual. The solutions manual says the answer is (2sin(10t+π/6)+1)μC. I got the same thing except +2 at the end since q(0) is 2. It's really bugging me that I can't figure out why. Can anyone please explain?
     
  2. jcsd
  3. Oct 2, 2014 #2

    Doc Al

    User Avatar

    Staff: Mentor

    If you plug in t = 0 to your solution and the manual's, which one gives the correct answer?
     
  4. Oct 2, 2014 #3
    Ahh, got it now. Thank you. I didn't realize that's what it meant. I was just adding the q(0) but I didn't realize until you pointed it out that the entire function in itself is q.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Very basic circuits 1 question. Charge and current
  1. Basic circuit question (Replies: 6)

  2. Basic circuit question (Replies: 3)

Loading...