document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=600886>Question 600886</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plane is flying at an altitude of about 7 miles above Earth. What is the measure of the arc that represents the part of Earth you can see? The radius of Earth is about 4000 miles.   Please help me. I have tried to do this problem many times but the concept confuses me. Thank you.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #379542 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=379542\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A plane is flying at an altitude of about 7 miles above Earth.<BR>\n" );
document.write( " What is the measure of the arc that represents the part of Earth you can see? The radius of Earth is about 4000 miles.<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Perhaps we can treat this as a \"distance to horizon\" problem, the observer is 7 mi above the earth<BR>\n" );
document.write( "One formula is: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+sqrt%28%283h%29%2F2%29 ALIGN=MIDDLE  ALT=\"d+=+sqrt%28%283h%29%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > where d is in miles and h is in feet<BR>\n" );
document.write( "Change 7 mi; 5280*7 = 36960 ft<BR>\n" );
document.write( "so we have<BR>\n" );
document.write( "d = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28%283960%2A3%29%2F2%29 ALIGN=MIDDLE  ALT=\"sqrt%28%283960%2A3%29%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "d ~ 235.5 mi<BR>\n" );
document.write( "looking in opposite directions a total of 2*235 = 471 mi can be viewed<BR>\n" );
document.write( "Find the circumference of the earth<BR>\n" );
document.write( "C = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi%2A8000 ALIGN=MIDDLE  ALT=\"pi%2A8000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "C = 25133 mi<BR>\n" );
document.write( ":<BR>\n" );
document.write( "The arc: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=471%2F25133 ALIGN=MIDDLE  ALT=\"471%2F25133\"   DISABLED_style= \"max-width:90%; height:auto;\" > * 360 = 6.7 degrees<BR>\n" );
document.write( ":<BR>\n" );
document.write( "This should be pretty close, because the earth is so large compared to the altitude.  would appreciate if it you would let me know. C </SPAN>\n" );
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