An 800-KHz Sinusoidal Radio Signal Is Detected at a Point $\vec { E }$

question 21

Multiple Choice

An 800-kHz sinusoidal radio signal is detected at a point 2.1 km distant from a transmitter tower.The $\vec { E }$ field amplitude of the signal at that point is 0.80 V/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 intensity of the radio signal at that point? (ε₀ = 8.85 × 10^-12 C²/N ∙ m²,μ₀ = 4π × 10^-7 T ∙ m/A,c = 3.0 × 10⁸ m/s)

• A)8.5 × 10^-4 W/m²
• B)1.2 × 10^-3 W/m²
• C)1.7 × 10^-3 W/m²
• D)6.0 × 10^-4 W/m²
• E)4.2 × 10^-4 W/m²

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Definitions:

Poker Time

A designated or scheduled period during which poker games are played, often referring to regular or tournament play times.

Standard Deviation

A mathematical indicator assessing the extent of spread within a collection of data points.

Sampling Distribution

The probability distribution of a statistic obtained from a large number of samples drawn from a specific population.

Normal Population

A population in statistics where all the individual measurements are symmetrically distributed around the mean, following a normal distribution.