document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=973477>Question 973477</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose I shot a rocket into the sky from a completely flat field and I was able to measure that the rocket reached a maximum height of 144 ft after 3 seconds. At the time of blast-off (time 0) the rocket was 0 feet high because it was on the ground.\r<BR>\n" );
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document.write( "1. given these two pieces of info find the formula for the height of the rocket at any time t. Note path of rocket is a parabola.  Is this standard form or should it be vertex form?\r<BR>\n" );
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document.write( "2. When does the model breakdown or no longer apply? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #595659 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=595659\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Suppose I shot a rocket into the sky from a completely flat field and I was able to measure that the rocket reached a maximum height of 144 ft after 3 seconds. At the time of blast-off (time 0) the rocket was 0 feet high because it was on the ground.\r<BR>\n" );
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document.write( "1. given these two pieces of info find the formula for the height of the rocket at any time t. Note path of rocket is a parabola.  Is this standard form or should it be vertex form?<BR>\n" );
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document.write( "The formula commonly used on Earth for projectiles is<BR>\n" );
document.write( "h(t) = -16t^2 + vt + h0 where v = launch speed and h0 = launch height.<BR>\n" );
document.write( "It's a parabola.<BR>\n" );
document.write( "Use whatever form is convenient.<BR>\n" );
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document.write( "h(3) = -16*9 + v*3 = 144<BR>\n" );
document.write( "v = 96 ft/sec<BR>\n" );
document.write( "For this example, h(t) = -16t^2 + 96t<BR>\n" );
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document.write( "2. When does the model breakdown or no longer apply?<BR>\n" );
document.write( "When it's a rocket, which has thrust and not just a projectile.  <BR>\n" );
document.write( "Why is this called a rocket? </SPAN>\n" );
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