document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=32194>Question 32194</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0534373526/algebrahomeworkh>College Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Kepler's Third Law of planetary motion states that the square of the period T of a planet (the time it takes for the planet to make a complete revolution around the sun) is directly proportional to the cube of its average distance d from the sun.<BR>\n" );
document.write( "a.) Express Kepler's Third Law as an equation.<BR>\n" );
document.write( "b.) Find the constant of proportionality by using the fact that for our planet the period is about 365 days and the average distance is about 93 million miles. <BR>\n" );
document.write( "c.) The planet Neptune is about 2.79 x 10^9 mi from the sun. Find the period of Neptune.\r<BR>\n" );
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document.write( "The equation I got is T^2/d^3, but for b and c I'm confused about the units.\r<BR>\n" );
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document.write( "Thank you all so very much! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #18747 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=18747\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a) T^2=kd^3<BR>\n" );
document.write( "b)365^2=k(9.3E7)^3<BR>\n" );
document.write( "k=[365^2]/[9.3E7)^3<BR>\n" );
document.write( "k=1.656...E-19<BR>\n" );
document.write( "c)T^2=[365^2/9.3E7^3][2.79E9]^3<BR>\n" );
document.write( "  T^2=7.8106E37<BR>\n" );
document.write( "  T=8.838E18 days per revolution<BR>\n" );
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