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**NOTICE: THIS IS NOT AN ACTUAL HOMEWORK PROBLEM.**

## Homework Statement

A projectile is launched from a hill 2m high 8m away from the base of a slanted wall at a velocity v at an angle of 35 degrees from the horizontal. The equation of the slanted wall is y = 2.8x. The slanted wall is 20m high. Ignore air resistance/drag and use g = -9.8m/s

^{2}. a) Where will the object collide with the slanted wall? Give (x,y) coordinates. b) What is the minimum velocity of the object needed to clear the wall? c) Give a mathematical representation of this problem where the angle the object is launched at is unknown.

## Homework Equations

s = s

_{0}+ v

_{0}t + 1/2gt

^{2}

http://en.wikipedia.org/wiki/Trajectory

http://en.wikipedia.org/wiki/Projectile_motion

http://en.wikipedia.org/wiki/Kinematics

## The Attempt at a Solution

I tried to solve this by representing the wall and the trajectory of the projectile graphically, but I'm only in high school level Physics, so I was absolutely clueless as to what equation I would use to represent the trajectory of the projectile so that the x axis was x displacement and the y axis was y displacement. (I googled a bit) I figured that if I graphed both of those equations the intersection point would be where the projectile hits the wall (so long as I changed the equation of the wall so it's x intercept is 8). Anyways, that didn't work out, and I've been wracking my brain as to how to solve this for 4 hours, help please!

P.S.: This is not an actual homework or classwork problem, I came up with this problem myself because I was trying to explain something that I saw in real life. ;]

Here is a diagram of the problem that I made in paint:

[PLAIN]http://img220.imageshack.us/img220/4765/diagramr.png [Broken]

The red curved line is my attempt at a parabola representing the trajectory of the projectile in the circumstance where the object comes in contact with the wall 2m above the ground.

Thanks,

Mator

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