document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1073701>Question 1073701</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boat is floating at rest in dense fog near a large cliff. The captain sounds a horn at water level and the sound travels through the salt water and the air (340 m/s) simultaneously. The echo in the water takes 0.40 seconds to return. How much additional time will it take the echo in the air to return?  \r<BR>\n" );
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document.write( "My solution: first find distance the boat is away from cliff\r<BR>\n" );
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document.write( "V = d/t \r<BR>\n" );
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document.write( "d = vt\r<BR>\n" );
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document.write( "speed of sound in salt water (according to text book) is 1470 m/s. \r<BR>\n" );
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document.write( "therefore d = (1470 m/s) (0.40s) <BR>\n" );
document.write( "d= 588 meters. \r<BR>\n" );
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document.write( "Now 588/2 = 294m   divide by 2 because sound travels to cliff then reflects back an equal distance\r<BR>\n" );
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document.write( "Now find the time in air\r<BR>\n" );
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document.write( "t= d/v <BR>\n" );
document.write( "t= 294m/340 m/s<BR>\n" );
document.write( "t= 0.86 seconds.\r<BR>\n" );
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document.write( "Finally, how much additional time in the air? \r<BR>\n" );
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document.write( "0.86 seconds - 0.40 seconds = 0.46 seconds.  \r<BR>\n" );
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document.write( "Am I correct? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #688491 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52905)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=688491\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "In your solution you didn't account that the sound wave in the air must go forward AND then return back.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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