Here is the question i am working on:(adsbygoogle = window.adsbygoogle || []).push({});

An AM radio station broadcasts with average power 4000 W in all directions. A dipole receiving antenna 65 cm long is at a location 4 miles from the transmitter. Compute the amplitude of the emp that is induced be this signal between the ends of the antenna.

I know that the intensity of power falls off as [tex]\frac{1}{r^2}[/tex] but i am not sure how to get the power at 4 miles.

i see on a website that intensity of an EM wave a distance r from the source is [tex]I=\frac{P_s}{4\pi r^2}[/tex] and also that [tex]I=\frac{I{E_{rms}}^2}{c\mu_0}[/tex]. I was thinking to equate these two expressions but i do not know what the I and Erms refer to in the second equation. thanks for the help.

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# Homework Help: Emf induced by EM wave

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