An $800 - \mathrm { kHz }$ Sinusoidal Radio Signal Is Detected at a Point

question 34

Multiple Choice

An $800 - \mathrm { kHz }$ sinusoidal radio signal is detected at a point $6.6 \mathrm {~km}$ from the transmitter tower. The electric field amplitude of the signal at that point is $0.780 \mathrm {~V} / \mathrm { m }$ . Assume that the signal power is radiated uniformly in all directions and that radio waves incident upon the ground are completely absorbed. What is the amplitude of the magnetic field of the signal at that point? $\left( \varepsilon _ { 0 } = 8.85 \times 10 ^ { - 12 } \right.$ $\mathrm { C } ^ { 2 } / \mathrm { N } \cdot \mathrm { m } ^ { 2 } , c = 3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } , \mu _ { 0 } = 4 \pi \times 10 ^ { - 7 } \mathrm {~T} \cdot \mathrm { m } / \mathrm { A }$ )

• A) \(2.6 \mathrm { nT }\)
• B) \(3.1 \mathrm { nT }\)
• C) \(3.6 \mathrm { nT }\)
• D) \(1.6 \mathrm { nT }\)
• E) \(2.1 \mathrm { nT }\)

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Definitions:

Proposition

A statement that expresses an idea or assertion which can be evaluated as true or false.

Standard Form

A recognized or typical format for presenting arguments or expressing certain types of information.

Proposition

A statement in logic that expresses a judgment or opinion and can be either true or false.

Disjunctive Proposition

A statement formed by combining two or more propositions with the word "or," indicating that at least one of the propositions is true.