1. Not finding help here? Sign up for a free 30min 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!

Rate of energy

  1. Oct 28, 2008 #1
    1. The problem statement, all variables and given/known data

    In a certain region of space, there is a uniform magnetic field B = 4.49 × 10−5 T, parallel to the x-axis, and a uniform electric field E = 10.2 V/m, parallel to the y-axis.
    The permeability of free space is 4 pi ×10−7 N · m2.
    At what rate does energy cross a square area, 0.65 cm on a side, that is perpendicular
    to the z-axis?
    Answer in units of W.

    2. Relevant equations

    I = EB / permeability

    P = IA

    3. The attempt at a solution

    I = (10.2 V/m)(4.49 e-5)/ (4*pi*e-7)
    =364.449 A

    P=(364.449 A) (0.0065 m)
    =2.36892 W

    This answer is not right when I plug it into my online homework answers. :(
  2. jcsd
  3. Oct 28, 2008 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    What is the area of the square?
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?