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## Homework Statement

My problem looks like this:

http://i.imgur.com/3M9wE43.png

I need to find the point of impact and the time the body traveled.

## Homework Equations

## The Attempt at a Solution

I tried to find the time for 25 meters and with that the vertical velocity and height.

Ended up getting: t at 25m = 1.96 s , h=16.83 m vi=-1.03 m/s

I tried this: hf=vx*sin37*t = 7.67 m/s*t , it should mean that for every seconds the slope rises 7.66m in height.

After that I set up: hf = h + vi*t - 1/2*g*t^2 and got:

7.67*t = 16.83 - 1.03*t - 4.905*t^2

-4.905*t^2 - 8.7*t + 16.83 = 0

4.905*t^2 + 8.7*t - 16.83 = 0

The positive t was 1.17 s

Total time = 1.96 s + 1.17 s = 3.13 s

Height:

h = vi*t - 1/2*g*t^2

h = 18.20 m/s * 3.13 s - 1/2 * 9.81 m/s^2 * (3.13s)^2

h = 8.91 m

distance = vx*t

distance = 12.75 m/s * 3.13 s = 39.9 m

My problem is that the height and distance doesn't match, the tangent of the angle is: height/distance = 8.91/39.9-25=8.91/14.9=0.5979 , with arctg I get around 31 degrees, shouldn't I get 37 degrees here? This is what bothers me. Is the method I used correct? If not, what is the method I should use to solve it?

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