document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1047148>Question 1047148</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The force needed to keep a car from skidding on a curve varies inversely as the radius of the curve and jointly as the weight of the care and the square of the speed.  It 247-lb of force keeps a 1200-lb car from skidding on a curve of radius 400 ft. at 35 mph, what force would keep the same car from skidding on a curve of radius 850 ft. at 60 mph?  <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 #662658 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=662658\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> F=k*(1/R)*M*V^2<BR>\n" );
document.write( "247=k*(1/400)*1200*35^2; (k can be different if we use ft/sec, but it will still give the same answer at the end)<BR>\n" );
document.write( "247/3675=0.06721<BR>\n" );
document.write( "F=0.06721*(1/850)*1200*60^2<BR>\n" );
document.write( "F=341.59 pounds or 342 pounds.<BR>\n" );
document.write( "Check.  The radius increases by about 2.1 approximately but the speed increases by 1.7^2 or about 2.9 , so this should increase the force by approximately 1.38.  The ratio is 1.38, which confirms it. </SPAN>\n" );
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