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:

Test Statistic

A value calculated from sample data during a hypothesis test, used to make a decision about the null hypothesis.

P-Value

A statistical measure that helps to determine the strength of the results to support or reject the null hypothesis.

Null Hypothesis

A hypothesis that assumes there is no statistical significance in a set of given observations and that any observed difference is due to sampling or experimental error.

P-Value

The probability of obtaining test results at least as extreme as the results actually observed, under the assumption that the null hypothesis is true.