document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=211170>Question 211170</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ths is a summer math problem I was assigned to complete. A punter can kick a football with an initial velocity of 48 feet per second. How many seconds will it take for the ball to return to the ground?(Hint: Use the formula h=vt-16t2*)I was unsure whether or not this formula was correct for some reason I thought the formula was h=v-16t2*. I still need help wth completing the problem though. Thank you in adance the sooner this is answered the better.\r<BR>\n" );
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document.write( "*The 2 in the problems above is a square. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #159534 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=159534\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  A punter can kick a football with an initial velocity of 48 feet per second. How many seconds will it take for the ball to return to the ground?(Hint: Use the formula h=vt-16t2*)I was unsure whether or not this formula was correct for some reason I thought the formula was h=v-16t2*.<BR>\n" );
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document.write( "It can't be h=v-16t^2, because the units don't match.<BR>\n" );
document.write( "h = distance and v is speed.  You can't add and subtract feet and feet/sec.<BR>\n" );
document.write( "Multiplying v*t gives feet/sec x 1/sec = feet.<BR>\n" );
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document.write( "h=48t-16t^2<BR>\n" );
document.write( "The ground is h = 0<BR>\n" );
document.write( "48t - 16t^2 = 0<BR>\n" );
document.write( "t*(48 - 16t) = 0<BR>\n" );
document.write( "t = 0 (at the start)<BR>\n" );
document.write( "t = 3 (return to the ground)<BR>\n" );
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document.write( "BTW, the -16t^2 term is acceleration due to gravity.  It's (gt^2)/2, where g is -32 ft/sec/sec.  <BR>\n" );
document.write( "Muliplying ft/sec/sec by sec^2 gives feet, so the units are uniform. </SPAN>\n" );
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