Review study questions

QUESTION 17 How are electrical signals and electromagnetic waves related? a. They are not related b. The current produced by an electrical signal traveling through a conductive wire creates an electromagnetic field c. Electrical signals produce acoustic energywhich travels through air in the form of an electromagnetic wave d. None of the above describe how the two are related QUESTION 18 An E-M wave consists of an electrical wave and a magnetic wave separated by 90 degrees. An E-M waye is created when a current travels along a wire. True False QUESTION 19 In unguided medium (free space), the electromagnetic (EM) signal wave spreads as it leaves the transmit antenna. Since the power of the EM signal resides at the surface area of the wave front, signal power is described as signal power density (i.e, watts per area) As the signal propagates away from the transmitter, power density decreases and attenuation is experienced. True False QUESTION 20 An ideal isotropic antenna is a theoretical antenna that propagates signal energy from a single point antenna. True False QUESTION 21 Select the correct statement regarding a. the passband signal is combined with the carrier wave to produce a baseband which operates at a higher frequency b. the carrier signal is combined with the passband wave to produce a baseband which operates at a higher frequency c. the passband signal is combined with the baseband wave to produce a carrier which operates at a higher frequency d. the baseband signal is combined with the carrier wave to produce a passband which operates at a higher frequency