Unit: wave phenomena
Year: 1989 Question#: 44
Question: Sound waves with a constant frequency of 250 hertz are traveling through air at STP. What is the wavelength of the sound waves?
(1 ) 0.76m
(2 ) 1.3m
(3 ) 250m
(4 ) 83,000m
What is this question really asking?
Explanation by: Meghan K.
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Answer 1
0.76m
Incorrect.
I am not sure what you have done wrong, or how you have arrived at this answer. I suggest that you plug in what you know to the formula for speed of sound. The formula is:
speed of sound = frequency X wavelength
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Answer 2
1.3m
Correct
The speed of sound in air equals 3.3 x 102 m/s. (in scientific notation) Speed of sound equals the product of its frequency and its wavelength.
3.3 x 102m/s = (250 hz)(wavelength)
330m/s divided by 250hz =wavelength
wavelength= 1.3 meters
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Answer 3
250m
Incorrect
I am not sure what you have done wrong, or how you have arrived at this answer. I suggest that you plug in what you know to the formula for speed of sound. The formula is:
speed of sound = frequency X wavelength
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Answer 4
83,000 m
Incorrect
Looks like you may have multiplied frequency times the speed of sound. Try using the formula and algebra more carefully. The formula is:
speed of sound = frequency X wavelength
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What's this question really asking?
How do you find wavelength when given frequency? How do you use the formula? return to top
