document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1128492>Question 1128492</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help; I am having great difficulty with this one.\r<BR>\n" );
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document.write( "Solve.&#8203; (Use 4.9t^2+v0t=&#8203;s.)\r<BR>\n" );
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document.write( "&#8203;a) A bolt falls off an airplane at an altitude of 500 m. Approximately how long does it take the bolt to reach the&#8203; ground?\r<BR>\n" );
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document.write( "&#8203;b) A ball is thrown downward at a speed of 10 &#8203;m/sec from an altitude of 500 m. Approximately how long does it take the ball to reach the&#8203; ground? \r<BR>\n" );
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document.write( "&#8203;c) Approximately how far will an object fall in 8 &#8203;sec, when thrown downward at an initial velocity of 10 &#8203;m/sec from a&#8203; plane? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #744975 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=744975\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Use 4.9t^2 + v0t = s\r<BR>\n" );
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document.write( "a) A bolt falls off an airplane at an altitude of 500 m. Approximately how long does it take the bolt to reach the ground?<BR>\n" );
document.write( "s = 4.9t^2 + v0t = 500<BR>\n" );
document.write( "4.9t^2 = 500<BR>\n" );
document.write( "t = sqrt(500/4.9) =~ 10.1 seconds<BR>\n" );
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document.write( "b) A ball is thrown downward at a speed of 10 m/sec from an altitude of 500 m. Approximately how long does it take the ball to reach the ground?<BR>\n" );
document.write( "Use s = -4.9t^2 + v0t --- It's -4.9t^2 as gravity acts downward<BR>\n" );
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document.write( "At impact, s = 0<BR>\n" );
document.write( "s = -4.9t^2 + 10t = 0<BR>\n" );
document.write( "t = 0 --- ignore<BR>\n" );
document.write( "t = 10/4.9 = 2.041 seconds at impact<BR>\n" );
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document.write( "c) Approximately how far will an object fall in 8 sec, when thrown downward at an initial velocity of 10 m/sec from a plane?<BR>\n" );
document.write( "s = -4.9t^2 - 10t --- both terms are downward --> both negative<BR>\n" );
document.write( "Sub 8 for t, find s </SPAN>\n" );
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