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AStaunton

- 105

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A circular loop of wire can be used as a radio antenna. If a 22.0-cm-diameter antenna is located 2.20km away from a 95.0-MHz source with a total power of 55.0kW, what is the maximum emf induced in the loop? (Assume that the plane of the antenna loop is perpendicular to the direction of the radiation's magnetic field and that the source radiates uniformly in all directions.)

As far as I have gotten in solving the problem:

as the loop of wire is at a distance of 2.2km from transmitter we want to find how much energy the loop of wire is getting:

((area of loop of wire)/(surface area of 2.2km sphere))*(power of transmitter)

and plugging numbers in (in mks units) gives:

((.11^2*pi)/(2200^2*pi)*55000) = 3.43*10^-5W

I would be very grateful for a nudge in the right direction...I'm fairly sure there must be a convenient equation derived from laws of inductance that links the power going through the loop, the Frequency (95Mhz) and the induced Voltage which is the variable I want to find.

Thanks

Andrew