The ionosphere, which
is the layer of atmosphere located in the region 50-5000 km above
the Earth, has a density of free electrons just like a metal.
a. if the free
electron density is 10^6 electrons per cubic centimeter, determine
the plasma frequency of the ionosphere in hertz (Hz)
b. a metal is
transparent to radiation with frequencies higher than the free
electron plasma frequency (this is usually in the ultraviolet
range), and reflect at lower frequencies. Determine the wavelengths...