document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1123912>Question 1123912</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help. Thankyou.<BR>\n" );
document.write( "A girl throws a ball vertically upward with a speed of 6.10 m/s from the roof of a building 18.29m high. a.) How long will it take the ball to reach the ground?  b.) What will its speed be when it reaches the ground? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #740300 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=740300\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A girl throws a ball vertically upward with a speed of 6.10 m/s from the roof of a building 18.29m high. a.) How long will it take the ball to reach the ground?  b.) What will its speed be when it reaches the ground?<BR>\n" );
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document.write( "You didn't supply the equation or function for the ball's position.<BR>\n" );
document.write( "9.8 m/sec/sec is commonly used on Earth in metric units.  Sometimes<BR>\n" );
document.write( " 10 m/sec/sec is used.<BR>\n" );
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document.write( "9.8 is closer to reality.<BR>\n" );
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document.write( "h(t) = -4.9t^2 + vo*t + h where vo is the upward speed at launch (not velocity) and h is the launch height.<BR>\n" );
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document.write( "a.) How long will it take the ball to reach the ground?  <BR>\n" );
document.write( "h(t) = -4.9t^2 + vo*t + h<BR>\n" );
document.write( "h(t) = -4.9t^2 + 6.1*t + 18.29<BR>\n" );
document.write( "-4.9t^2 + 6.1*t + 18.29 = 0 at impact<BR>\n" );
document.write( "Solve for t (ignore the negative solution).<BR>\n" );
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document.write( "b.) What will its speed be when it reaches the ground?<BR>\n" );
document.write( "Speed is the 1st derivative of position.<BR>\n" );
document.write( "h'(t) = -9.8t + 6.1<BR>\n" );
document.write( "Use the value for t from part a. </SPAN>\n" );
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