Energy in electromagnetic waves

Thread starter map7s
Start date Mar 26, 2007
Tags

Electromagnetic Electromagnetic waves Energy Waves

AI Thread Summary

To find the electric and magnetic field amplitudes in an electromagnetic wave with an average energy density of 3.0 J/m3, the relevant equations include u = 1/2 ε₀ E² + 1/(2μ₀) B² and u = ε₀ E². The user initially struggled with applying these equations correctly and questioned whether unit conversion was necessary. Ultimately, they resolved the issue independently but sought confirmation on the correct approach. The discussion highlights the importance of understanding the relationships between electric and magnetic fields in electromagnetic waves.

Mar 26, 2007

map7s

Homework Statement

Find the electric and magnetic field amplitudes in an electromagnetic wave that has an average energy density of 3.0 J/m3.

Homework Equations

u=1/2 eo E^2 + 1/(2uo) B^2
u=eo E^2
u=B^2 /uo

The Attempt at a Solution

I tried using these equations, but I wasn't getting the right answer. Do I have to change the units or am I just using the wrong equations?

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Mar 26, 2007

map7s

just kidding...I figured it out :)

Apr 1, 2008

Combatchuck

how do you do it?!

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