Impulse Momentum Lab Report 281g15

Drew Beathard Quackenbush 12-1-14 Impulse-Momentum Lab Report Purpose: The purpose of this experiment is to the impulse momentum theorem. We will go about doing this by calculating the theoretical impulse for an experiment and then comparing it to the experimental impulse after collecting data. The theoretical impulse, as calculated by ∑F∆t, should match up with the experimental impulse, as measured by mvf-mvi. The association between these two calculated variables will prove the formula shown below. ∑F=M x A ∑F= M x ∆V/∆T ∑F x ∆T= M x ∆V ∑F x ∆T= MVf-MVi Equipment:  2 photo gates  Cart  Ramp  String  Weights Procedure: 1. Measure mass of cart and weight, and width of cart wing. 2. Place ramp on table and place cart on ramp. Tie one end of the string to the cart and the other end to the weights, and hang the weights over the end of the ramp. 3. Run three trials with photo gates at x=0cm and x=15cm. 4. Run three trials with photo gates at x=0cm and x=30cm. 5. Run three trials with photo gates at x=0cm and x=45cm. 6. Run three trials with photo gates at x=0cm and x=60cm. 7. Record time AB for time from photo gate A to B to calculate velocity for each trial setup. 8. Calculate velocity by dividing width of cart wing by photo gate time. 9. Calculate the impulse of each of the three trial setups with mvfmvi and with ∑F∆t and compare calculations. Diagram of Experiment Setup: String

Photo Gate B

Photo Gate A

Ramp Weight

Cart

Data Collection: Mass cart 0.3287 kg

Mass plates 0.5837 kg

Displacement (cm) 15cm 30cm 45cm Displacement (cm) 60cm 15cm 30cm Displacement (cm) 45cm 15cm 60cm 30cm 45cm 60cm Displacement (cm) 15cm 30cm 45cm 60cm

Net Force 5.72 N

Wing Length (m) 0.049

Time A (s) Trial 1 Trial 2 Trial 3 Average 0.019 0.019 0.019 9 9 9 0.0199 0.020 0.020 0.020 8 8 8 0.0208 0.028 0.028 0.028 Time 8 B (s) 8 7 0.028766667 Trial 1 Trial 2 Trial 3 Average 0.043 0.042 0.042 1 0.018 7 0.018 8 0.042866667 0.018 0.01833333 2 4 4 0.018 0.018 0.018 4 3 6 0.01843333 Time AB (s) 0.018 0.017 0.018 Trial 4 1 Trial 52 Trial 33 0.01806667 Average 0.057 0.018 0.057 0.018 0.056 0.057066667 0.018 4 8 2 1 1 0.01813333 0.077 0.077 0.078 0.0776 1 5 2 0.205 0.202 0.203 9 8 9 0.2042 0.315 0.314 0.315 7 6 6 0.3153

Initial Velocity Final Velocity (m/s) (m/s) 2.462311558 2.672727273 2.355769231 2.658227848 1.703360371 2.712177122 1.143079316 2.702205882

Data Analysis: Conclusion: In this lab procedure, we measured the experimental impulse and theoretical impulse of a force acting on a cart, and compared the two in order to the impulse momentum theorem. Although the data we collected for theoretical (∑F∆t) and experimental (mvf-mvi) were not the same, they showed similar trends and proved that the equations are closely related. The differences in the data can only be explained by errors produced by those conducting the experiment and inaccuracies with the design. The data calculated for the theoretical impulse is one with no other forces acting upon it, and no energy lost. As we know, factors such as friction between the wheels and the pulley, and air resistance, cause the calculations of the experimental impulse to change. When these forces go uned for as they were in this experiment, the data is skewed. Another variable that is uned for is the mass of the string. The formulas we used to calculate the theoretical impulse do not for the mass of the string, and therefore the experimental impulse is affected. The third major factor causing major differences between the theoretical and experimental impulses is human error. It is impossible to release the car the exact same way each time. This causes the cart to leave at slightly different velocities each trial. There are several ways to make this experiment more effective and accurate. The first is using an object that has less friction between the surfaces; although the cart had ball bearing wheels, friction energy was lost during movement. A second method of improving the experiment would be to use a more consistent release mechanism; each time the cart was released during data collection, it was not released the same way. I think that the best way to do this would be by using an archery release. The simple press of the trigger on the mechanism releases instantly with no energy lost. Because there were so many external forces causing the data to differ, the experiment did not necessarily prove the impulse momentum theorem. It did show noticeable association and shows the relation of the two formulas. In order to conduct an experiment that can truly the impulse momentum theorem, we will have to make a design that limits factors causing data to be skewed.