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Question
Solve the following problem.
A certain sound wave in air has a speed 340 m/s and wavelength 1.7 m for this wave, calculate
- the frequency
- the period
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Solution
Given: v = 340 m/s, λ = 1.7 m
To find: frequency (n), period (T)
Formulae:
- n = `"v"/lambda`
- T = `1/"n"`
Calculation: From formula (i),
n = `340/1.7`
∴ n = 200 Hz
From formula (ii),
T = `1/200 = 1/(2 xx 10^2)`
= 5 × 10-3 ....(using reciprocal table)
∴ T = 0.005 s
The frequency of the sound wave is 200 Hz and its period is 0.005 s.
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