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3 years ago

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Sound waves travel in air at 343 m/s. The lowest frequency one can hear is 25.0 Hz; the highest frequency is 25.0 kHz. Find the

wavelength of sound for 25.0 Hz and 25.0 kHz

1 answer:

Slav-nsk [51]3 years ago

8 0

Answer:

13.72 m and 0.01372 m respectively

Explanation:

Wavelength: This can be defined as the distance covered in one complete oscillation. The S.I unit of wavelength is meter (m).

The formula for the speed of a wave is given as

v = λf ............................. Equation 1

Where v = speed of the sound wave, λ = wavelength, f = frequency of the sound wave.

make λ the subject of the equation,

λ = v/f ......................... Equation 2

For the lowest frequency,

Given: f = 25 Hz, v = 343 m/s.

Substitute into equation 2

λ = 343/25

λ = 13.72 m.

For the highest frequency,

Given: f = 25 kHz = 25000 Hz, v = 343 m/s

Substitute into equation 2

λ = 343/25000

λ = 0.01372 m.

The wavelength of sound for 25 Hz and 25 kHz = 13.72 m and 0.01372 m respectively

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