document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=644068>Question 644068</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The force F with which a magnet attracts a steel ball is inversely proportional to the square of the distance d of the ball from the magnet. If the steel ball is now 8 cm from the magnet, how far from the magnet should it be placed to attain an attracting force 4 times as great as its present attracting force? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #404869 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=404869\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The force F with which a magnet attracts a steel ball is inversely proportional to the square of the distance d of the ball from the magnet.<BR>\n" );
document.write( "That means we can write F as a function of d as<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F%28d%29=K%2Fd%5E2 ALIGN=MIDDLE  ALT=\"F%28d%29=K%2Fd%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > , with <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=K ALIGN=MIDDLE  ALT=\"K\"   DISABLED_style= \"max-width:90%; height:auto;\" > being some constant.<BR>\n" );
document.write( "If the steel ball is now 8 cm from the magnet, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d=8 ALIGN=MIDDLE  ALT=\"d=8\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and the force would be<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F%288%29=K%2F8%5E2=K%2F64 ALIGN=MIDDLE  ALT=\"F%288%29=K%2F8%5E2=K%2F64\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "We want to attain an attracting force 4 times as great as its present attracting force, meaning a force of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2A%28k%2F64%29=K%2F16 ALIGN=MIDDLE  ALT=\"4%2A%28k%2F64%29=K%2F16\"   DISABLED_style= \"max-width:90%; height:auto;\" > , so we need to find <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d ALIGN=MIDDLE  ALT=\"d\"   DISABLED_style= \"max-width:90%; height:auto;\" > so that<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F%28d%29=K%2Fd%5E2=K%2F16 ALIGN=MIDDLE  ALT=\"F%28d%29=K%2Fd%5E2=K%2F16\"   DISABLED_style= \"max-width:90%; height:auto;\" > <--> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5E2=16 ALIGN=MIDDLE  ALT=\"d%5E2=16\"   DISABLED_style= \"max-width:90%; height:auto;\" > <--> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28d=4%29 ALIGN=MIDDLE  ALT=\"highlight%28d=4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );