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CBSE Class 9 Answered

a source of wave produces 20 crests and 20 troughs in 0.2 seconds.distance between a crest and next trough is 50cm.find wavelength and frequency.
Asked by aditi sharma | 22 Feb, 2012, 09:49: PM
answered-by-expert Expert Answer
Distance between two successive crusts or troughs is knowns as wavelength So Wavelength = 100 cm (because distance between crust & trough is 50 cm) In 0.2 seconds, it complete 20 waves in 1 second , it will complete 20 * 5 = 100 crests. So Frequency is 100 Hz.
Answered by | 23 Feb, 2012, 10:16: AM

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