I took a practice PP&D exam and got the following question that seems oddly worded and possibly think incorrect:
A sound of 30 dB is how many times more intense that a sound intensity of 10dB?
A) 10 dB
B) 100 dB
C) 20 dB
D) 50 dB
The correct response was B "Each increase of 10dB is a two-fold increase in sound level intensity. There for two two-fold increases would be 10x10 which equals 100."
This seems oddly worded and I don't really understand this. If 100 is correct, then wouldn't the correct response be 100 and not 100dB. the units shouldn't be there I don't think. I mean how could a 20dB difference be 100 dB louder? From what I've read each time it increases by 10dB it would essentially be 10 exponent 1, so 10dB to 20 dB would be 10 exponent 2= 10x10=100 times louder, then again at 30dB I think so it would be then 1000 times as loud? I'm not sure. Please review and advise. I appreciate the clarification.
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