Julian Yuliawan, Sean Kondas
Energy: Conversion and Conservation Abstract
The experiment performed was a test of the theory of conversion and conservation of energy for the elastic collisions of two steel balls. The apparatus used included two identical steel balls, a projectile launcher, and a pendulum. The distance traveled by a ball launched using potential energy stored in a spring was compared to the distance traveled by a ball launched using gravitational potential energy. Also, the ranges of the two launching methods were compared with the predicted ranges. Results showed that on average, the pendulum launched the projectile further than the launcher meaning that there was more gravitational potential energy stored as opposed to potential energy stored in the spring. Introduction
The experiment utilized a tape measure to measure the distance traveled by the projectile after the elastic collision. To find the predicted range of a projectile that has an initial velocity only in the x­direction, the formula: x=Vox
√2h/g was used. The range of the launcher was found by using the formula: r=2x/m+1
√(2hpk/mcg), and the range of the pendulum was found by using the formula: r=4/m+1
√hchp. The experimental ranges of the pendulum and launcher were then compared to the predicted ranges to determine whether the same amount of energy imparted to the projectile by two different sources causing it to travel the same distance. Procedure
The projectile was loaded into the launcher using the plunger, making sure that the launcher was on the short­range setting. The projectile ball was then placed in front of the launcher. The string was pulled to launch the colliding ball, and then the distance traveled by the projectile ball was measured. This was process was repeated for 5 trials. Next for the pendulum, the projectile ball was placed in the middle of a wooden block. The colliding ball hung on the end of the pendulum was then raised to a height of 40 cm and then released to launch the projectile ball. The distance of the projectile ball after the elastic collision was then measured.
This process was repeated for 5 trials. Data Range

Predicted

Launcher
Pendulum

T­1

T­2

T­3

T­4

T­5

Average

r

.357m

.34m .35m .33m .31m

.35m

.336m

.014 m .357m

.42m .42m .44m .41m

.35m

.408m

.014 m Analysis
The results obtained from this experiment were relatively accurate, but there was much still much room for improvement. The predicted values for the ranges of the collisions from the launcher and the pendulum both turned out to be .357m using the given equations. This predicted value was used as the model to determine and analyze the error in the