When a guitar string is struck, a standing wave is produced that oscillates with a large sustained amplitude, pushing back and forth against the surrounding air to generate sound. How does the frequency of the resulting sound compare with the frequency of the standing wave in the string? 1. The frequencies of the resulting sound have nothing to do with those of the standing wave in the string. 2. The frequencies of the resulting sound are half of those of the standing wave in the string. 3. The frequencies of the sound and the oscillating string are the same. 4. The frequencies of the resulting sound are twice of those of the standing wave in the string.4

3) True. The box is built to amplify the frequencies ,

Explanation:

When the guitar string is played, a wave is produced along it with a wavelength given by the root of the relationship between the tension and the linear density of the string. This frequency moves the air that is in the vicinity and this air creates a wave that enters a soundboard, designed to amplify the waves of the string; therefore the frequencies of the string and the air are the same.

Let's check the answers

1) False. The soundboard is built to amplify the frequency of the string

2) False. They are equal

3) True. The box is built to amplify the frequencies

4) False. They are equal

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