document.write( "Question 962834: Remember the definition of a decibel:\r
\n" ); document.write( "\n" ); document.write( "dB=10log(I×10^12)\r
\n" ); document.write( "\n" ); document.write( "where dB is the magnitude on the decibel scale and I is the intensity of the sound wave. If a quiet whisper is 30 dB and the sound of a train whistle is 90 dB, how many times more intense is the sound of a train whistle than a whisper? \n" ); document.write( "

Algebra.Com's Answer #588260 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
whisper:
\n" ); document.write( " $\"+30+=+10%2Alog%28+I%2A10%5E12+%29+\"$
\n" ); document.write( " $\"+log%28+I%2A10%5E12+%29+=+3+\"$
\n" ); document.write( " $\"+10%5E3+=+10%5E12%2AI+\"$
\n" ); document.write( " $\"+I+=+10%5E3%2A10%5E%28%28-12%29%29+\"$
\n" ); document.write( " $\"+I+=+10%5E-9+\"$
\n" ); document.write( "------------------
\n" ); document.write( "train whistle:
\n" ); document.write( " $\"+90+=+10%2Alog%28+I%2A10%5E12+%29+\"$
\n" ); document.write( " $\"+log%28+I%2A10%5E12+%29+=+9+\"$
\n" ); document.write( " $\"+10%5E9+=+10%5E12%2AI+\"$
\n" ); document.write( " $\"+I+=+10%5E9%2A10%5E%28%28-12%29%29+\"$
\n" ); document.write( " $\"+I+=+10%5E-3+\"$
\n" ); document.write( "-------------------
\n" ); document.write( " $\"+10%5E-3+=+k%2A10%5E-9+\"$
\n" ); document.write( " $\"+k+=+10%5E-3+%2F+10%5E-9+\"$
\n" ); document.write( " $\"+k+=+10%5E-3%2A10%5E9+\"$
\n" ); document.write( " $\"+k+=+10%5E6+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "the train whistle is 10^6 or
\n" ); document.write( "one million times more
\n" ); document.write( "intense than the whisper
\n" ); document.write( " \n" ); document.write( "

\n" );