document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1122062>Question 1122062</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I've being going round and round with this question, but cannot get it right.\r<BR>\n" );
document.write( "\n" );
document.write( "The weight of a body &#119908; varies inversely with the square of its distance from the center of Earth &#119889;. If a person weighs 90 pounds on the surface of Earth, what is the person’s weight 160 miles above the surface? (Assume that the radius of Earth is 4000 miles.)\r<BR>\n" );
document.write( "\n" );
document.write( "In our text it says Inversely means multiply, and so I did,(yz=k):\r<BR>\n" );
document.write( "\n" );
document.write( "90(160)^2=k<BR>\n" );
document.write( "90(25600)=k<BR>\n" );
document.write( "2304000=k\r<BR>\n" );
document.write( "\n" );
document.write( "The part of the question that has me confused is when it talks about radius of the earth being 4000 miles. \r<BR>\n" );
document.write( "\n" );
document.write( "I assumed it would be used as follows:\r<BR>\n" );
document.write( "\n" );
document.write( "4000m/4000 = 2304000/4000\r<BR>\n" );
document.write( "\n" );
document.write( "which gives an answer of: m = 576\r<BR>\n" );
document.write( "\n" );
document.write( "This seems incorrect.\r<BR>\n" );
document.write( "\n" );
document.write( "Any advice would be appreciated. \r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #738100 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=738100\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The weight of a body &#119908; varies inversely with the square of its distance from the center of Earth &#119889;. If a person weighs 90 pounds on the surface of Earth, what is the person’s weight 160 miles above the surface? (Assume that the radius of Earth is 4000 miles.)<BR>\n" );
document.write( "----------<BR>\n" );
document.write( "You have to use the distances from the Earth's center.<BR>\n" );
document.write( "--> 90*(4000/4160)^2<BR>\n" );
document.write( "===================<BR>\n" );
document.write( "It's a typical inverse square problem.<BR>\n" );
document.write( "Applies to gravity, sound, light, etc.<BR>\n" );
document.write( "If the distance is multiplied by x, the intensity is multiplied by 1/x^2<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );