document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=788873>Question 788873</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In a test your strength booth at a fair you strike a pad with a hammer. This projects a weight up a vertical slide. A bell rings if you have hit the pad hard enough . When the pad is struck with just sufficient force to ring the bell the height h in metres of the weight r seconds after the pad is struck is given h = 8t-4.9r^2.\r<BR>\n" );
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document.write( "a) How high is the weight 0.5 seconds after the pad is struck?<BR>\n" );
document.write( "b) How high is the bell?\r<BR>\n" );
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document.write( "Can you please help me out? Thanks so much in advance:)<BR>\n" );
document.write( "Can you also please show the steps it would really help me understand:) 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 #478630 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=478630\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> When the pad is struck with just sufficient force to ring the bell the height h in metres of the weight r seconds after the pad is struck is given h = 8t-4.9r^2. <BR>\n" );
document.write( "a) How high is the weight 0.5 seconds after the pad is struck?<BR>\n" );
document.write( "h(0.5) = 8*0.5 - 4.9(0.5)^2 = 2.775 meters.<BR>\n" );
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document.write( "b) How high is the bell?<BR>\n" );
document.write( "The bell could be 3 miles high. But the weight will reach its<BR>\n" );
document.write( "peak when t = -b/(2a) = 8/(2*4.9) = 0.8163 seconds<BR>\n" );
document.write( "When t = 0.8163 the height is 8*4 - 4.9*0.8163^2 = 28.73 ft<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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