document.write( "Question 1007759: With what velocity will a stone strike the ground if dropped from the top of the building 400 ft high?Solve by integration. \n" ); document.write( "

Algebra.Com's Answer #623595 by rothauserc(4718) $\"\"$ $\"About$

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dv / dt = a and integrating this we get
\n" ); document.write( "v = c + at where c is initial velocity, a is acceleration of gravity and t is time
\n" ); document.write( "in our problem c is 0 since the stone is dropped and a = 32 feet/sec^2
\n" ); document.write( "now distance covered is the integration of v with respect to time, so
\n" ); document.write( "we integrate v = at and get
\n" ); document.write( "distance = (1/2)at^2, therefore
\n" ); document.write( "400 = (1/2)* 32 * t^2
\n" ); document.write( "t^2 = 800 / 32
\n" ); document.write( "t = 5 seconds, now
\n" ); document.write( "v = 32 * 5 = 160 feet per second when the stone hits the ground \n" ); document.write( "

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