## CatapultBy: zach, kaleb, and Eli

This is the design route we took for our catapult.

### Data

Maximum height average 7 feet and 4 inches. All of our data points 20 feet 7/12, 18 feet 2/12, 17 feet 2/12, and 18 feet 6/12.

Maximum range average 18 feet and 5 inches. All of our data points 7 feet 1/12, 8 feet 7/12, 6 feet 10/12, and 6 feet 2/12.

### Final equation

y = -0.080 (x-9.2038) + 7.33

### Question after initial launch

1. Our catapult is launching consistently. Each launch we completed was between 17 and 20 feet. The reason our catapult is launching consistently is because we are pulling the arm back the same amount each time we test it. Also, we are using the same person for every launch so we have consistent numbers.

2. To make our launch more consistent we could measure the degree at which we pull back the arm. This would ensure that our data points would be as accurate as possible. We would still have the same person launch the catapult.

3. A revision that we could make to improve the distance of our catapult is to add more rubber bands on the arm. Adding more rubber bands would increase the maximum distance that the catapult could shoot.

4. We need to place a target at around 18 feet and 5 inches because that is the average distance that our catapult can shoot. Doing this would increase our chance of hitting the target.

### Questions before final launch

1. Our projectile hit the ground at around 18 feet and 5 inches according to our equation. This is because the average landing point for our projectile was 18 feet and 5 inches. We know this is true because when we shoot our catapult it would always land around 18 feet.

2. The maximum height of the ball we shot was between 6 and 8 feet. The maximum height occurred halfway through the path the ball took in the air or the vertex. The vertex is basically the middle point of the balls trajectory. It takes place after the ball travels up and before the ball starts to decline.

3. The height that the ball is at when it has traveled 6 feet is 6 feet and 5 inches. We know this is true because we plugged in 6 feet for the x value to find the y value. Once you have found your equation you can just plug in the x or the y and find the other value.

4. To make the vertex of the ball greater we would have to pull the arm on the catapult further back. This would increase the amount of tension in the rubber bands which would therefor increase the height of the ball. If you pull the arm back further, the ball will travel higher but will fall faster as a result.