document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=896373>Question 896373</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1.) you're in a diving competition on the 3m springboard. you hit the water (3m below board) 1.6 seconds after you leave the board. \r<BR>\n" );
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document.write( "a. what's the initial upward velocity?\r<BR>\n" );
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document.write( "b. when do you pass the board again on the way down?\r<BR>\n" );
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document.write( "c. how high above the board did you go?\r<BR>\n" );
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document.write( "d. if another person steps off the 10m platform at the same time as you jump for the dive, who hits the water first? how much sooner?\r<BR>\n" );
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document.write( "2.) clare can paint a fence in 14 hours. john can paint the same fence in 12 hours. mr smith can paint the fence in 18 hours. if all 3 work together, how long will it take the three people to paint the fence?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #543449 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=543449\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1.) you're in a diving competition on the 3m springboard. you hit the water (3m below board) 1.6 seconds after you leave the board.<BR>\n" );
document.write( "You didn't spec a function.<BR>\n" );
document.write( "h(t) = -4.9t^2 + vot + h is commonly used with metric units.\r<BR>\n" );
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document.write( "a. what's the initial upward velocity?<BR>\n" );
document.write( "h(t) = 0 at t = 1.6 seconds<BR>\n" );
document.write( "-4.9*1.6^2 + vo*1.6 + 3 = 0<BR>\n" );
document.write( "1.6vo = 7.84 - 3 = 4.84<BR>\n" );
document.write( "vo = 3.025 m/sec<BR>\n" );
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document.write( "b. when do you pass the board again on the way down?<BR>\n" );
document.write( "h(t) = -4.9t^2 + vot + h = 3<BR>\n" );
document.write( "h(t) = -4.9t^2 + 3.025t + 3 = 3<BR>\n" );
document.write( "Solve for t<BR>\n" );
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document.write( "c. how high above the board did you go?<BR>\n" );
document.write( "h(t) = -4.9t^2 + vot + h is a parabolic function.<BR>\n" );
document.write( "Find the vertex<BR>\n" );
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document.write( "d. if another person steps off the 10m platform at the same time as you jump for the dive, who hits the water first? how much sooner?<BR>\n" );
document.write( "h(t) = -4.9t^2 + 3.025t + 3 = 0 for you.<BR>\n" );
document.write( "h(t) = -4.9t^2 + 0t + 3 for the other person.<BR>\n" );
document.write( "Solve for t and compare.<BR>\n" );
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document.write( "2.) clare can paint a fence in 14 hours. john can paint the same fence in 12 hours. mr smith can paint the fence in 18 hours. if all 3 work together, how long will it take the three people to paint the fence?<BR>\n" );
document.write( "In 1 hour, Clare does 1/14, John does 1/12 and Smith does 1/18.<BR>\n" );
document.write( "1/t = 1/14 + 1/12 + 18<BR>\n" );
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