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: Mechanical waves - average power transmitted

  1. Jul 30, 2009 #1
    1. The problem statement, all variables and given/known data
    show, using the propagating wave y = Ae^[i(wt - kx)] that the average power transmitted across any point on the string in a complete full cycle is given by P = vE (P and E are both vectors). v is the phase velocity and E the total average energy density per cycle. also show that div(P) + dE/dt = 0 for the wave. Here E is the total energy density and P is the directed instantaneous power transmitted across a point.

    2. Relevant equations
    in the question statement

    3. The attempt at a solution
    i don't even know where to begin! i have run out of internet cap (this is my last little bit of data for the month) and i don't have a text book - and there are none left in the library. my lecturer's notes are quite useless too, as they don't explain anything i need for this question. if anyone could help me i would really appreciate it, i'm totally lost!
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted