document.write( "Question 214250: A car is parked on a cliff overlooking the ocean
\n" ); document.write( "on an incline that makes an angle of 18.0◦
\n" ); document.write( "below the horizontal. The negligent driver
\n" ); document.write( "leaves the car in neutral, and the emergency
\n" ); document.write( "brakes are defective. The car rolls from rest
\n" ); document.write( "down the incline with a constant acceleration
\n" ); document.write( "of 2.00 m/s2 and travels 43.0 m to the edge of
\n" ); document.write( "the cliff. The cliff is 40.0 m above the ocean.
\n" ); document.write( "The acceleration of gravity is 9.81 m/s2 .
\n" ); document.write( "a) How long is the car in the air? Answer
\n" ); document.write( "in units of s.\r
\n" ); document.write( "\n" ); document.write( "b) What is the car’s position relative to the
\n" ); document.write( "base of the cliff when the car lands in the
\n" ); document.write( "ocean? Answer in units of m.\r
\n" ); document.write( "\n" ); document.write( "whats steps would u take to solve this problem
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Algebra.Com's Answer #162156 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
A car is parked on a cliff overlooking the ocean
\n" ); document.write( "on an incline that makes an angle of 18.0◦
\n" ); document.write( "below the horizontal. The negligent driver
\n" ); document.write( "leaves the car in neutral, and the emergency
\n" ); document.write( "brakes are defective. The car rolls from rest
\n" ); document.write( "down the incline with a constant acceleration
\n" ); document.write( "of 2.00 m/s2 and travels 43.0 m to the edge of
\n" ); document.write( "the cliff. The cliff is 40.0 m above the ocean.
\n" ); document.write( "The acceleration of gravity is 9.81 m/s2 .
\n" ); document.write( "a) How long is the car in the air? Answer
\n" ); document.write( "in units of s.
\n" ); document.write( "b) What is the car’s position relative to the
\n" ); document.write( "base of the cliff when the car lands in the
\n" ); document.write( "ocean? Answer in units of m.
\n" ); document.write( "-----------------------------
\n" ); document.write( "s = (at^2)/2
\n" ); document.write( "43 = (2*t^2)/2
\n" ); document.write( "t = sqrt(43) seconds to go the 43 meters
\n" ); document.write( "v = at = 2sqrt(43) m/sec when the car leaves the incline and is airborne.
\n" ); document.write( "v =~ 13.114877 m/sec
\n" ); document.write( "------------
\n" ); document.write( "The vertical component of v is v*sin(18) = -4.05272 m/sec (neg since is down)
\n" ); document.write( "The horizontal part of v is v*cos(18) = 12.473 m/sec
\n" ); document.write( "---------------------
\n" ); document.write( "h(t) = -9.81t^2 - 4.05272t + 40
\n" ); document.write( "h(0) = 40 (when it leaves the ground)
\n" ); document.write( "Find t at h = 0 (when it hits the water)
\n" ); document.write( "-9.81t^2 - 4.05272t + 40 = 0
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"-9.81x%5E2%2B-4.05272x%2B40+=+0\") has the following solutons:
\n" ); document.write( "
\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%28-4.05272%29%5E2-4%2A-9.81%2A40=1586.0245393984\".
\n" ); document.write( "
\n" ); document.write( " Discriminant d=1586.0245393984 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--4.05272%2B-sqrt%28+1586.0245393984+%29%29%2F2%5Ca\".
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-4.05272%29-sqrt%28+1586.0245393984+%29%29%2F2%5C-9.81+=+1.8232519671579\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"-9.81x%5E2%2B-4.05272x%2B40\" can be factored:
\n" ); document.write( " \"-9.81x%5E2%2B-4.05272x%2B40+=+%28x--2.23637327194893%29%2A%28x-1.8232519671579%29\"
\n" ); document.write( " Again, the answer is: -2.23637327194893, 1.8232519671579.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+-9.81%2Ax%5E2%2B-4.05272%2Ax%2B40+%29\"

\n" ); document.write( "\n" ); document.write( "t =~ 1.823252 seconds
\n" ); document.write( "----------------------
\n" ); document.write( "The horizontal part of v is v*cos(18) = 12.473 m/sec
\n" ); document.write( "12.473 m/sec * 1.823252 seconds =~ 22.741 meters from the base of the cliff
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