Posted by Sam on Thursday, September 23, 2010 at 2:34pm.
A projectile is launched from ground level to the top of a cliff which is 195 m away and 155 m high. If the projectile lands on top of the cliff 9.2 s after it is fired, find the initial velocity of the projectile (magnitude and direction). Neglect air resistance. Also calculate the angle

Physics  bobpursley, Thursday, September 23, 2010 at 2:44pm
Well, you have some algebra ahead.
Vertical:
155=VsinTheta*t4.9t^2
Horizontal:
195=VcosTheta*t
you are given t.
So you have two equations, two unknowns.
Here is what I suggest. Put both equations in the form of
V*trigfunction=some number
then square both sides.
add the equations, you should get something like this:
V^2(cosTheta ^2 + sinTheta ^2)=number^2
well, you know the ( ) is 1, which allows you to solve for V. Then substitute back to solve for theta.
Have fun.