What is the formula for calculating average power of electromagnetic waves?

AI Thread Summary
The formula for calculating the average power of electromagnetic waves is Savg = Em * Bm / (2*μ0 * c), where Savg represents average power, Em is the maximum electric field, and Bm is the maximum magnetic field. The discussion clarifies that when calculating Savg, only the maximum values of the electric and magnetic fields are necessary, making the result independent of frequency or position. The confusion regarding whether to solve inside the cosine function is addressed, confirming that it is not required for this calculation. The provided maximum electric field value of 4.6 volts per meter is sufficient for solving the problem. Overall, understanding the significance of maximum field values is key to calculating average power in electromagnetic waves.
blackbyron
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Homework Statement



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Homework Equations


Savg = Em * Bm / (2*μ0 * c)


The Attempt at a Solution


I solved for S avg without calculating inside the cos, but I got it right.

The z and t is given, but is there the reason why you don't solve inside the cos, or is it the bug? it's makes me confused.

Thanks
 
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Savg = Em * Bm / (2*μ0 * c)

What do Savg, Em and Bm mean?

ehild
 
I see, I look at my teacher's notes and saw the exact equation.

So to solve for Savg, it only cares about the maximum values right?
 
Right, the result is independent of frequency or position.
 
Thanks for your help.
 

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