A bat produces a sound with a frequency of 17,250 Hz and a wavelength of 0.019 m. What is the speed of this sound?
A1.7 x 10^6 m/s
B8.6 x 10^5 m/s
C3.28 x 10^2 m/s
D1.15 x 10^-6 m/s
Answer & Solution
Correct answer: C. 3.28 x 10^2 m/s
1. Identify the knowns: f = 17,250 Hz and lambda = 0.019 m.
2. Use v = f x lambda to find the speed of sound.
3. Substitute the SI values: v = 17,250 Hz x 0.019 m = 327.75 m/s, which rounds to 3.28 x 10^2 m/s.
4. This matches option C.
5. Option A, 1.7 x 10^6 m/s, results from dividing frequency by wavelength instead of multiplying them.
6. Option B, 8.6 x 10^5 m/s, is roughly double the correct product, consistent with an arithmetic slip in the multiplication.
7. Option D, 1.15 x 10^-6 m/s, results from dividing wavelength by frequency, the inverse of the correct operation.
_Source: OpenStax Physics (CC BY 4.0), Ch 14 "Sound", section 14.1 Speed of Sound, Frequency, and Wavelength_
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