document.write( "Question 1034139: Please help me solve this probem. I know the answer is after about 1.75 seconds, but I do not know the steps to get that answer. ...We are studying projectile motion. Maddie served a volleyball from 1 meter off the ground with an upward velocity of 8 meters per second.
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Algebra.Com's Answer #648747 by ikleyn(52797)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "Please help me solve this problem. I know the answer is after about 1.75 seconds, but I do not know the steps to get that answer. ...
\n" ); document.write( "We are studying projectile motion. Maddie served a volleyball from 1 meter off the ground with an upward velocity of 8 meters per second.
\n" ); document.write( "If no-one touches the ball, when will it hit the ground?
\n" ); document.write( "Thanks in advance!
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document.write( "Only vertical component of the velocity is relevant to this problem.\r\n" );
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document.write( "The equation describing the height of the ball above the ground in this problem is\r\n" );
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document.write( "\"%28-9.8%2F2%29t%5E2+%2B+8t+%2B+1\" = \"0\",  or  (which is the same)\r\n" );
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document.write( "\"-4.9t%5E2+%2B+8t+%2B+1\" = \"0\".     (1)\r\n" );
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document.write( "Here t is the time the volleyball is in the air, and \"0\" in the right side is the ground level.\r\n" );
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document.write( "Solve this quadratic equation for t, and choose an appropriate root.\r\n" );
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document.write( "Now a bit more explanation.\r\n" );
document.write( "If the object is thrown vertically with the initial vertical velocity \"v\" from the initial height \"h%5B0%5D\", its height h(t) is a quadratic function\r\n" );
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document.write( "h(t) = \"-%28gt%5E2%29%2F2+%2B+vt+%2B+h%5B0%5D\".    (2)\r\n" );
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document.write( "It will hit the ground when h(t) = 0.\r\n" );
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document.write( "Here \"g\" is the gravity acceleration, also known as \"free fall acceleration\"\r\n" );
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document.write( "The value for g is about 9.81 \"m%2Fs%5E2\" near the Earth surface.\r\n" );
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document.write( "Based on this info, the equations (1) and (2) above are written.\r\n" );
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document.write( "Now solve the quadratic equation (1) and get your answer.\r\n" );
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document.write( "What I explained to you, is part of Physics. \r\n" );
document.write( "In this compact form it is necessary information for solving this kind of problems in Algebra.\r\n" );
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\n" ); document.write( "\n" ); document.write( "If you have questions, don't hesitate to ask in this site.\r
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\n" ); document.write( "\n" ); document.write( "This plot shows you the height of the ball above the ground as a function of time.\r
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\n" ); document.write( "\n" ); document.write( "Can you see from the plot WHEN the volleyball will hit the ground?\r
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\n" ); document.write( "\n" ); document.write( "Figure. Plot h(t) = \"-%289.8%2F2%29t%5E2+%2B+8t+%2B+1\"\r
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