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

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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.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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