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23 Nov 2019

The loudness level of a 20 Hz sine wave which sounds just as loudas 1000 Hz, 70 dB sine wave is

a. greater than 70 phons
b. 70 phons
c. less than 70 phons
d. less than 70 dB

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Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

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If you know the sound level in dB, then you can compute the soundintensity and take the ratio.


Helpful Hint*
In the problem, they gave the intensity as decibels but want toknow by what factor to increase the intensity (I) for the youngperson to get a sound that the older person can hear.

Ignore f completely.

Decibels (dB) need to be converted to I using this equation:
I=(10^(dB/10))*10^-12
Do this for each dB and divide the older person's dB by theyounger's.


Thank you for all your help.

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