A Sound Source Approaches a Stationary Observer

question 4

Multiple Choice

A sound source approaches a stationary observer. The frequency heard by the observer is

• A) higher than the source.
• B) lower than the source.
• C) the same as that of the source.
• D) equal to zero.
• E) impossible to predict.

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Definitions:

Marginal Benefit

The increase in utility or enjoyment an individual gets by consuming an additional unit of a good or service.

Marginal Cost

The extra expense associated with creating an additional unit of a product or service.

Streetlights

Outdoor lighting fixtures installed along streets to provide illumination during the night to enhance visibility and safety.

Marginal Social Benefit

The additional benefit to society from consuming or producing one more unit of a good or service.