(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A cannon shoots a ball from the origin. There is a wall of 17.58 meters 67.5 meters away. The ball needs to clear the wall just barely and hit a person sitting on the ground 12 meters behind the wall. No air resistance. What is the degree the ball is launched at. No max height or initial velocities are given. Just two various lengths and height of the wall.

2. Relevant equations

position= x+vt+1/2at^2 (applies to both x and y)

gravity is 9.8 m/s^2 in the negative y direction

Vy=(2gh)^1/2

3. The attempt at a solution

Using properties of parabolas I know I have 4 points on the curve and I used those four points to get the quadratic equation. Using that I found the max height and used the basic formulas to find the initial velocity and used the two vectors of x and y velocity to find the angle that the ball is launched and got 59.9 degrees which is the correct answer. My professor however told me that i couldn't do it that way and had to find a different way to do this problem using what I know about projectile motion.

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# Homework Help: Projectile Motion with few variables

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