A Source Emits Sound with a Frequency of 1000 Hz

question 48

Multiple Choice

A source emits sound with a frequency of 1000 Hz. It is moving at 20 m/s toward a stationary reflecting wall. If the speed of sound is 340 m/s an observer at rest directly behind the source hears a beat frequency of:

• A) 11 Hz
• B) 86 Hz
• C) 97 Hz
• D) 118 Hz
• E) 183 Hz

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Definitions:

Rail

A mode of transportation that involves the movement of goods or passengers on trains along a set of tracks.

Carrier

A company or individual that provides transportation services for goods or people.

Straight Bill Of Lading

A document issued by a carrier that specifies the goods being transported are to be delivered to the specified party, without endorsement.

Negotiable Instrument

A document guaranteeing the payment of a specific amount of money, either on demand or at a set time, with the payer named on the document.