Concept explainers
High-frequency signals are often transmitted along a coaxial cable, such as the one shown in FIGURE CP3O.86. For example, the cable TV hookup coming into your home is a coaxial cable. The signal is carried on a wire of radius
a. Find an expression for the inductance per meter of a coaxial cable. To do so, consider the flux through a rectangle of length l that spans the gap between the inner and outer conductors.
b. Evaluate the inductance per meter of a cable having
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