document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1204872>Question 1204872</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Earthquakes produce several types of shock waves. The most well known are the P-waves (P for primary or pressure) and the S-waves (S for secondary or shear). In the earth's crust, P-waves travel at about 6.5 km/s and S-waves move at about 3.5 km/s. The time delay between the arrival of these two waves at a seismic recording station tells geologists how far away an earthquake occurred. If the time delay is 33 seconds, how far from the seismic station did the earthquake occur? \r<BR>\n" );
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document.write( "(problem from Young and Freedman. University Physics with Modern Physics. Fifteenth Edition) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #841407 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=841407\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Time taken by S waves - time taken by P waves =  33 s\r<BR>\n" );
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document.write( "Let the distance earthquake occured be x km\r<BR>\n" );
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document.write( "Time taken by P waves x/6.5 seconds\r<BR>\n" );
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document.write( " time taken by s waves =  x/3.5 seconds\r<BR>\n" );
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document.write( "x/3.5-x/6.5= 33\r<BR>\n" );
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document.write( "6.5x-3.5x = 6.5*3.5*33\r<BR>\n" );
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document.write( "3x =750.75\r<BR>\n" );
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document.write( "x=750.75/3\r<BR>\n" );
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document.write( "x= 250.25 Km\r<BR>\n" );
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document.write( "The distance the earth quake occured\r<BR>\n" );
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document.write( " </SPAN>\n" );
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