Field Intensity: an 800-KHz Radio Signal Is Detected at a Point

question 20

Multiple Choice

Field intensity: An 800-kHz radio signal is detected at a point 8.5 km distant from a transmitter tower. The electric field amplitude of the signal at that point is 0.90 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 average electromagnetic energy density at that point? (c = 3.0 × 10⁸ m/s, μ₀ = 4π × 10^-7 T ∙ m/A, ε₀ = 8.85 × 10^-12 C²/N ∙ m²)

• A) 3.6 pJ/m³
• B) 5.1 pJ/m³
• C) 7.2 pJ/m³
• D) 10 pJ/m³
• E) 14 pJ/m³

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Definitions:

Organization

A structured group of individuals working together to achieve common goals.

Poisson Probability Distribution

Describes the probability of a given number of events happening in a fixed interval of time or space when these events occur with a known constant mean rate.

Business Processes

A set of tasks and activities that are sequentially organized to achieve a specific organizational goal or objective.

Independent Events

Two or more events where the occurrence of one does not affect the probability of the others.