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Total Power Radiated

  • Thread starter PassThePi
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  • #1
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What is the total power radiated by an isotropic source in free space is |E| = 1mV/m at a distance of 10km?

Relevant Eqns:
Prad(theta,phi,r) = (1/2)*eta*|E|^2

Prad(theta,phi,r) = (1/2)*377*0.001^2*(10000) = 1.885mV

Is this correct? I feel like it can't be that simple.
 
Last edited:

Answers and Replies

  • #2
4,261
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Your 1mV/m is measured at a point 10Km away, to calculate the total power of the isotropic source( E is equal in magnitude at any point on the sphere), you need to have some sort of integration of the whole surface of radius of 10Km.

I don't understand your formula at all!!!
 
Last edited:
  • #3
5
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Oh I think I see...

Prad(theta,phi,r) = (1/2)*eta*|E|^2

Prad(theta,phi,r) = (1/2)*377*0.001^2*(10000) = 1.885mV

PradTotal = (int(0|2*pi))(int(0|pi))(Prad(theta,phi,r)*r2sin(theta)dtheta*dphi

PradTotal = 2*pi*0.132*(-cos(\0|pi)) = 0.528*pi
 

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