Question 1
The Young's modulus for aluminum is 7.02 × 1010 N/m2. If the speed of sound in aluminum is measured to be 5.10 km/s, find its density (in kg/m3).
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11.3 × 103
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7.80 × 103
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2.70 × 103
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29.3 × 103
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1.40 × 103
Question 2
To decrease the intensity of the sound you are hearing from your speaker system by a factor of 36, you can
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reduce the amplitude by a factor of 12 and increase your distance from the speaker by a factor of 3.
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reduce the amplitude by a factor of 4 and increase your distance from the speaker by a factor of 3.
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reduce the amplitude by a factor of 2 and increase your distance from the speaker by a factor of 3.
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reduce the amplitude by a factor of 3 and increase your distance from the speaker by a factor of 4.
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reduce the amplitude by a factor of 3 and increase your distance from the speaker by a factor of 12.