_Lab Report Collision

Raymond Guan November 17, 2014 Period 7 AP Physics I LAB Report SECTION I: INTRODUCTION TITLE: PHET Collision Lab OBJECTIVE: I hope to successful analyze collision of an object when elasticity and inelasticity are involved. Also, when different forces are applied and be able to understand what is occurring. EQUIPMENT NEEDED: ● Computer ● pHet Collision ● Two Balls ● Force PROCEDURE: 1. Open up Collision and Momentum Lab 2. Set up page to look like the instructed 3. Set elasticity to 100% 4. Predict with the current conditions, the effects of Collision 1 5. Hit play, and watch what occurs. Record the results and compare to your predictions. 6. Reset all, and change the masses, initial velocities to your own accordnace and record and compare. Do this trial twice with the new changes. 7. Change to elasticity to between 1 and 99 8. Repeat steps 4 - 6 with the new elasticity and see what happens. 9. Change elasticity to 0 and redo the collision application. 10. Calculate your kinectic energy 11. Record data and conclude SECTION II: DATA Mass of object 1= 1kg initial v of 1= 1m/s initial p of 1 = 1m Mass of object 2= 2kg initial v of 2 = 0m/s initial p of 2 = 2m The total amount of momentum didn’t change because the energy was transferred from the first ball to the second ball, so the amount of momentum was equal throughout. Elasticity = 50% Total initial p= 3m

START COLLISION Mass of object 1= 1kg final v of 1 = 0m/s final p of 1 = 1.66m Mass of object 2= 2kg final v of 2 = 0.5m/s final p of 2 = 4.50m Did total momentum arrow change? Yes/no No, the total momentum arrow did not change. Although ball one did stop, there was no change. Total final p= 6.15m Experiment 2 Pick a new non-zero, non-1.00 elasticity and run again Mass of object 1= 1kg initial v of 1= 1m/s initial p of 1 = 1m Mass of object 2= 2kg initial v of 2 = 0m/s initial p of 2 = 2m Elasticity = 6% Total initial p= 3m START COLLISION Mass of object 1= 1kg final v of 1= 0.29m/s final p of 1 = 2.96m Mass of object 2= 2kg final v of 2= 0.35 m/s final p of 2 = 3.56m Did total momentum arrow change? Yes/no No, the total momentum arrow did not change again, because there's elasticity that keeps their shape so their was no change in shape that would alter the total momentum. Total final p= 6.52m Experiment 3 Now set Elasticity to exactly 0.00 Mass of object 1= 1 kg initial v of 1 = .29 m/s initial p of 1 =.29kg m/s Mass of object 2= 2 kg initial v of 2 = .35m/s initial p of 2 = .71kg m/s Elasticity = 0 Total initial p=1 kg m/s START COLLISION Mass of object 1=1 final v of 1 = .29 m/s final p of 1 =.29 kg m/s Mass of object 2 = 2 final v of 2 = .35 m/s final p of 2 = .71kg m/s Did total momentum arrow change? Yes/no Total final p= no Calculate you kinetic energy’s before and after collisions now when you are not fully elastic. 1. Is Kinetic Energy conserved now? If so when No, because in inelastic collisions, kinetic energy is not conserved. It is being changed to some other form of energy. It would only be fully conserved if the collision was complete elastic. 2. Did your total momentum ever change? If so when?

po= 3m pf= -7.15m #2 m1 v01 p01 m2 v02 p02 vf1 pf1 vf2 pf2 predi ction s 2kg 12m/ s 1m 2kg 0m/s 2m 0m/s -5m .78m/ s 4m result s 0m/s 1.62 m 12m/ s 85.09 m po= 3m pf= 86.71m #3 m1 v01 p01 m2 v02 p02 vf1 pf1 vf2 pf2 predi ction s .5kg 1m/s 2m .2kg 0m/s 2.5m 17m/ s -5m .69m/ s 21m result s .43m/ s 5.36 m 1.43 m/s 12.74 m po= 4.5m pf= 18.1m CALCULATIONS: 1/2m1u² + 1/2m2(0)² = 1/2m1v1² + 1/2m2v2² ½(.5kg)u² + ½(.2kg)(0)² = ½(.5kg)(1m/s)² + ½(.2kg)(0m/s)² ½(.2kg)u² + ½(2kg)(0)² = ½(2kg)(12m/s)² + ½(2kg)(0m/s)² RESULTS: We were able to examine the collision of balls in multiple settings of inelasticity and elasticity. Also,we were able to see the momentum of forces during collisions and how it changed. For a elasticity of of 100%, the total kinectic energy was conserved meaning the total force applied to the balls were transferred as energy. We started with a velocity of 12m/s and 0m/s on the second ball. After the

collision, the first with a mass of 1kg hitting the 25kg had a -0.92 m/s and the second one had a 0.08 velocity. Inelasticity or 0% resulted in loss of kinetic energy. The balls would stick together and go indefinitely on. The final velocity was .43m/s and the fina velocity of the second ball was 1.43m/s. CONCLUSION: I was able to reach my objective and I fully understand collisions and momentum. I was able to understand elasticity when applied to real life examples. Kinetic energy was also learned because of the conservation of energy was applied when deailing with elasticity. It would determine whether the energy remained or changed. I learned the use of the program as well as the different forces exerted on object for it to move up a ramp with forces like gravity acting on it. The creation of the free body diagrams really helped me understand further the details of motion on a object in a collision. At first, when the box wouldn’t move at 10N or even 100N of force, I thought it was broken, but when we raised it to the threshold it moved the box significantly at a distance. The threshold being 491N for the crate. I was able to examine the forces needed to move objects.