Sound intensities in hearing aids

AI Thread Summary
The discussion focuses on calculating the decibel increase produced by a hearing aid with a sound gathering area of 900cm² and an eardrum area of 0.5cm², considering a transmission efficiency of 5%. The relationship between power and intensity is highlighted, emphasizing that power collected at the input is transmitted to the output with the specified efficiency. The initial confusion regarding the calculation method is resolved when the original poster corrects a mistake made on their calculator. Ultimately, the thread underscores the importance of understanding the relationship between sound intensity and area in hearing aid performance. Accurate calculations are crucial for determining the effectiveness of hearing aids.
slaw155
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What decibel increase does a hearing aid produce if its sound gathering area is 900cm^2, the area of the eardrum is 0.5cm^2, but it only has an efficiency of 5% in transmitting sound to the eardrum?

I know sound level = 10log(final intensity/initial intensity), but we've only been given areas, so I don't know how to convert these into intensities to find change in sound level?
 
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I think you'll say that the power it collects at the input is transferred across to the output, with an efficiency of 5%.

Q: How is Power related to Intensity?

You don't happen to have been given the correct answer? It's always handy ...
 
Thanks solved it turns out I made a mistake on my calculator.
 

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