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Question
In a standing wave pattern in a vibrating air column, nodes are formed at a distance of 4.0 cm. If the speed of sound in air is 328 m s−1, what is the frequency of the source?
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Solution
Given:
Distance between two nodes = 4 cm
Speed of sound in air v = 328 ms−1
Frequency of source f = ?
Wavelength λ = 2 × 4.0 = 8 cm
v = fλ
\[\therefore f = \frac{v}{\lambda} = \frac{328}{8 \times {10}^{- 2}} = 4 . 1 \text { KHz }\]
Hence, the required frequency of the source is 4.1 KHz.
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