document.write( "Question 1103806: according to the national association of rocketry the current model rocket altitude record in the f altitude events for ages 14 through 18 division is 1430 meters. from this record-setting altitude, the rocket is motionless as it begins his free fall the sat back to the ground using the equations, h (t)=-4.9t^2+v^0t+h^0find how long it will take here for the rocket to hit the ground after reaching its high point. (Hint: motionless implies and hitting the ground implies) \n" ); document.write( "

Algebra.Com's Answer #718497 by ikleyn(52780) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "

\r\n" );
document.write( "It to omit all the literature, or, better to say, if translate this literature to Math or Physics, it means the following:\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "    How long it will take for freely falling body to hit the ground from the height of 1430 meters.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Using the equation h(t) = -4.9*t^2 + 0*t + 1430  (where \"0\" means the zero initial velocity, or motionless condition at the highest point \r\n" );
document.write( "of the trajectory),\r\n" );
document.write( "\r\n" );
document.write( "getting ground level means h(t) = 0,  so you need to solve this quadratic equation\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "-4.9*t^2 + 0*t + 1430 = 0,   or\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "4.9*t^2 = 1430  ====>  t^2 =  = 291.9  ====>  t =  = 17.1 seconds (approximately).\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Answer.  17.1 seconds (approximately).\r\n" );
document.write( "

\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );