An antenna located on the surface of a flat earth transmits an average power of 200 kW. Assuming that all the power is radiated uniformly over hte surface of a hemisphere with the antenna at the center, the time average Poynting vector at 50 km is

\(\frac{2}{\pi }\;{\bar a_r}W/{m^2}\)

\(\frac{2}{\pi }\;{\bar a_r}\mu \;W/{m^2}\)

An antenna located on the surface of a flat earth transmits an average

1.	An antenna located on the surface of a flat earth transmits an average power of 200 kW. Assuming that all the power is radiated uniformly over hte surface of a hemisphere with the antenna at the center, the time average Poynting vector at 50 km is
A.	Zero
B.	\(\frac{2}{\pi }\;{\bar a_r}W/{m^2}\)
C.	\(\frac{40}{\pi }\;\mu W/m^2\)
D.	\(\frac{2}{\pi }\;{\bar a_r}\mu \;W/{m^2}\)
Answer» E.

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An antenna located on the surface of a flat earth transmits an average power of 200 kW. Assuming that all the power is radiated uniformly over hte surface of a hemisphere with the antenna at the center, the time average Poynting vector at 50 km is

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