document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=203468>Question 203468</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9780073533490/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> 68. Telephoto lens. Use the formula from Exercise 67 to find<BR>\n" );
document.write( "the image distance i for an object that is 2,000,000 mm from<BR>\n" );
document.write( "a 250-mm telephoto lens.\r<BR>\n" );
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document.write( "it is the formula 1/f=1/o+1/i\r<BR>\n" );
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document.write( "thanks so much<BR>\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 #153550 by </B><A HREF=/tutors/aboutme.mpl?userid=psbhowmick><B>psbhowmick(878)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=psbhowmick><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=psbhowmick><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=153550\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Ff=1%2Fo%2B1%2Fi ALIGN=MIDDLE  ALT=\"1%2Ff=1%2Fo%2B1%2Fi\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "where f = focal length, o = object distance, i = image distance<BR>\n" );
document.write( "Given, o = 2000000 mm, f = 250 mm.<BR>\n" );
document.write( "Substituting these in the given equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F250=1%2F2000000%2B1%2Fi ALIGN=MIDDLE  ALT=\"1%2F250=1%2F2000000%2B1%2Fi\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Fi=1%2F2000000+-+1%2F250 ALIGN=MIDDLE  ALT=\"1%2Fi=1%2F2000000+-+1%2F250\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Fi=%281-8000%29%2F2000000 ALIGN=MIDDLE  ALT=\"1%2Fi=%281-8000%29%2F2000000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=i=-2000000%2F7999=-250 ALIGN=MIDDLE  ALT=\"i=-2000000%2F7999=-250\"   DISABLED_style= \"max-width:90%; height:auto;\" > mm (approximately)\r<BR>\n" );
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document.write( "P.S.: The minus sign indicates that the object and image are on the opposite sides of the lens. </SPAN>\n" );
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