document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=702146>Question 702146</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A domed ceiling is a parabolic surface. FOr the best lighting on the floor, a light source is to be placed at the focus of the surface. If 5 m down from the top of the dome ceiling is 3 m wide, find the best location for the light source. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #432859 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=432859\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A domed ceiling is a parabolic surface. FOr the best lighting on the floor, a light source is to be placed at the focus of the surface. If 5 m down from the top of the dome ceiling is 3 m wide, find the best location for the light source.<BR>\n" );
document.write( "**<BR>\n" );
document.write( "Draw a parabola facing down with the vertex (top of the dome) at the origin (0,0)<BR>\n" );
document.write( "Equation for this parabola: x^2=-4py<BR>\n" );
document.write( "Using coordinates (1.5,-5), 5 m down from the top where the ceiling is 3 m wide,<BR>\n" );
document.write( "x^2=4py<BR>\n" );
document.write( "1.5^2=-4p(-5)<BR>\n" );
document.write( "2.25/5=4p<BR>\n" );
document.write( "4p=0.45<BR>\n" );
document.write( "p=0.1125<BR>\n" );
document.write( "location for the light source: 0.1125 m below the dome(vertex) on the axis of symmetry(x=0) </SPAN>\n" );
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