Two In-Phase Loudspeakers That Emit Sound with the Same Frequency

question 138

Multiple Choice

Two in-phase loudspeakers that emit sound with the same frequency are placed along a wall and are separated by a distance of 8.00 m.A person is standing 12.0 m away from the wall,equidistant from the loudspeakers.When the person moves 3.00 m parallel to the wall,she experiences destructive interference for the second time.What is the frequency of the sound? The speed of sound in air is 343 m/s.

• A)278 Hz
• B)422 Hz
• C)452 Hz
• D)562 Hz
• E)694 Hz

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Definitions:

Continental Crust

The substantial section of the Earth's crust that creates the major continental areas, typically older and more intricate than the crust found beneath oceans.

Oceanic Crust

The thin layer of crust that forms the ocean floors, primarily composed of basalt and gabbro, and denser than continental crust.

Uppermost Mantle

The top layer of the Earth's mantle, directly beneath the Earth's crust, involved in tectonic plate movements and magma generation.

Isostasy

The condition of equilibrium, comparable to floating, of the crust resting on the solid mantle.