Because of the Doppler Effect, the Sound of the Engines

question 207

Multiple Choice

Because of the Doppler effect, the sound of the engines of an aircraft that flies past an observer

• A) changes from a high pitch or frequency to a lower pitch as the plane passes the observer.
• B) changes from a low pitch or frequency to a higher pitch as the plane passes the observer.
• C) remains at the same pitch or frequency, but the intensity rises as the plane approaches and then falls as the plane moves away.
• D) starts at a high pitch or frequency, drops to a low frequency when the plane is overhead, then rises again as the plane moves away.

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Definitions:

Built-In Mechanism

An inherent procedure, function, or process that is an integral part of a system or organism, often referring to biological or psychological processes.

Sleep-Waking Cycle

The natural, cyclical pattern of alternating states of sleep and wakefulness in a 24-hour period.

Near-Polar Region

Areas close to the North or South Pole, characterized by extreme cold temperatures, unique ecosystems, and seasonal variations in daylight.

Severe Health Problems

Significant or life-threatening conditions that require intensive medical intervention.