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Question
Waves produced on the surface of the water are formed to move with a velocity of 24 ms−1. If the wavelength of these waves equals 20 cm. find the
(i) frequency (no. of waves produced per second)
(ii) the time period (i.e. the time required to produce one wave) for these waves.
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Solution
(i) We have,
Wave velocity = Frequency × Wavelength
24 ms−1 = n × (20 × 10−2 m)
or n = `24/(24xx10^-2)` = 120 per second.
(ii) Time period = `1/"Frequency"=(1/120)"sec."` = 0.00833 sec.
The approximate frequency range of sound waves is about 15 to 200,000 Hz.
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