document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=907693>Question 907693</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The load L that a helical spring can support varies directly as the cube of its wire<BR>\n" );
document.write( "diameter d and inversely as its coil diameter D. A spring for which d = 0.1 cm and D =<BR>\n" );
document.write( "0.9 cm can support 50 N. What is the coil diameter of a similar spring that supports<BR>\n" );
document.write( "78.5 N and for which d = 0.2 cm?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #550506 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=550506\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The load L that a helical spring can support varies directly as the cube of its wire  diameter d and inversely as its coil diameter D.<BR>\n" );
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document.write( "L = kd^3/D<BR>\n" );
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document.write( "Solve for \"k\" using \"A spring for which d = 0.1 cm and D = 0.9 cm can support 50 N.\"<BR>\n" );
document.write( "50 = k*0.1^3/0.9<BR>\n" );
document.write( "45 = 0.001k<BR>\n" );
document.write( "k = 45000<BR>\n" );
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document.write( "Equation:<BR>\n" );
document.write( "L = 45000*d^3./D<BR>\n" );
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document.write( "What is the coil diameter of a similar spring that supports<BR>\n" );
document.write( " 78.5 N and for which d = 0.2 cm?<BR>\n" );
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document.write( "78.5 = 45000*0.2^3/D<BR>\n" );
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document.write( "D = 45000*0.2^3/78.5<BR>\n" );
document.write( "D = 4.59 cm<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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