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प्रश्न
The wavelength of waves produces on the surface of water is 20 cm. If the wave velocity is 24 m s-1, calculate:
- the number of waves produced in one second, and
- the time in which one wave is produced.
उत्तर
(i) Frequency or the number of waves produced per second
= `"Velocity"/"Wavelength"`
= `24/(20 × 10^-2`
= 120 Hz
(ii) Time = `1/ "frequency"`
= `1/120`
= 8.3 × 10-3 seconds
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