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Question
The speed of a wave in a certain medium is 900 m/s. If 3000 waves passes over a certain point of the medium in 2 minutes, then compute its wavelength?
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Solution
Speed (v) = 900 m/s
No. of. waves produced in 120 sec (2 min) = 3000
∴ In 1 sec (f) = `3000/120`
To find: λ = ??
Formula: `lambda = "V"/"f" = 900/(3000/120)` = 36 m
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