document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1090222>Question 1090222</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given the Earth's radius of 4000 miles, and a mass of 200 pounds:<BR>\n" );
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document.write( "The weight on the surface is 200 pounds.<BR>\n" );
document.write( "What is the weight in an elevator to the Earth's center at various depths?<BR>\n" );
document.write( "Depth of 500 miles, 1000 miles, 2000 miles, etc.<BR>\n" );
document.write( "-\Ignore any effects of pressure and temperature.<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 #704654 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52835)</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=704654\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "When (and if) the body is placed inside the Earth at the radius \"r\" (the depth R-r), then the only the part of the Earth <BR>\n" );
document.write( "which is inside of the sphere of the radius \"r\" creates (produces)  the gravity.\r<BR>\n" );
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document.write( "The exterior spherical layers  r < s < R  produce ZERO gravity integral force.\r<BR>\n" );
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document.write( "In other words, they do not make gravity force.\r<BR>\n" );
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document.write( "This fact is known from the Newton times to all who know/knows Physics.\r<BR>\n" );
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document.write( "And this effect MUST be accounted for in the solution of problems like this one.\r<BR>\n" );
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document.write( "The situation (and the solution) is different comparing with the case when the body is lifted ABOVE the Earth surface.\r<BR>\n" );
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document.write( "Therefore, the solution by @Fombitz is incorrect and must be redone.\r<BR>\n" );
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document.write( "To get the feeling of this effect, imagine that the body is placed exactly at the center of the (spherical) Earth.\r\n" );
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document.write( "What is the gravity force and what is its direction in this case ?\r\n" );
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document.write( "The answer (quite unexpected ?)  is: the gravitation force is ZERO in this case.\r\n" );
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document.write( "          Did I say \"unexpected\" ?  - But if you think 5-10 seconds on it, you will get that is is correct \r\n" );
document.write( "                                      and nothing else can happen (due to symmetry).\r\n" );
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