A Sound Source of Frequency 1,090 Hz Moves at 40

question 69

Multiple Choice

A sound source of frequency 1,090 Hz moves at 40 m/s toward a listener who is at rest.What is the apparent frequency heard by the listener? (speed of sound = 340 m/s)

• A) 1,218 Hz
• B) 962 Hz
• C) 980 Hz
• D) 1,240 Hz
• E) ​861 Hz

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Definitions:

Assistance

The provision of help or support, often aimed at solving a problem or completing a task.

Unassisted

Without help or support from others or external resources.

Crawl

The action of moving on all fours, typically the initial means of locomotion for infants before they learn to walk.

Walk Backward

The ability to move in a reverse direction by taking steps with the back leading, typically developed in early childhood.