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Question
The string of a guitar is 80 cm long and has a fundamental frequency of 112 Hz. If a guitarist wishes to produce a frequency of 160 Hz, where should the person press the string?
Solution
Data: L1 = 80 cm, n1 = 112 Hz, n2 = 160 Hz
According to the law of length, n1L1 = n2L2.
∴ The vibrating length to produce the fundamental frequency of 160 Hz,
L2 = `("n"_1"L"_1)/"n"_2=(112(80))/160` = 56 cm
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