A car manufacturer claims an enginerring breakthrough, since it successfully reduced its interior noise level from 65dB to 55 dB. What might be a proper reaction?

Question

BlackTom AI · Accepted Answer

The question presents a claim about reducing interior noise from 65 dB to 55 dB and asks for a proper reaction. To reason through the options, we need to recall how decibels relate to sound intensity.
Option 1: 'A 10 dB reduction? That's just a 10% reduction in noise intensity.' This mixes up the logarithmic scale. A 10 dB drop does not correspond to a 10% reduction in linear intensity; it corresponds to a roughly tenfold (90%) reduction in intensity. Therefore this statement is inaccurate.
Option 2: 'Yes, that's quite remarkable --- they cut the intensity of the noise by 90%!'
This is correct in quantitative terms. A decrease of 10 dB from 65 dB means the sound intensity is reduced by a factor of 10, which is a 90% reduction in intensity. The decibel scale is logarithmic, so a 10 dB change represents a tenfold change in intensity, not a linear 10% change, making this a proper reaction.
Option 3: 'That's not much; the intensity of the noise only dropped by a factor of 10/65, or about 15%.'
This statement incorrectly assesses the drop. It treats the change as a simple linear ratio of intensities rather than a logarithmic difference. The actual factor is 10 dB, which equates to a tenfold change in intensity, not 10/65, and the percent reduction is about 90%, not 15%.
In summary, the key misconception in options 1 and 3 is treating decibels as a linear measure of intensity. Decibels reflect a logarithmic relation, so a 10 dB decrease from 65 dB corresponds to a 90% reduction in sound intensity, making option 2 the accurate characterization while options 1 and 3 misinterpret the scale.

A car manufacturer claims an enginerring breakthrough, since it successfully reduced its interior noise level from 65dB to 55 dB. What might be a proper reaction? 单项选择题

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