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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?
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Solution
Given: L1 = 80 cm
n1 = 112 Hz
n2 = 160 Hz
According to the law of length:
n1L1 = n2L2
L2 = `(n_1 L_1)/n_2`
= `(112 (80))/160`
= 56 cm
∴ The guitarist must press the string so that the vibrating length becomes 56 cm.
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