PHYSICS EFFICIENCY LAB

Manipulated: Responding: Controlled: "Hint there is exactly 1 manipulated and 1 responding variable. There are many controlled variables. Procedure: 1) Research the mass of each ball online. Find a result which looks appropriate based on the object you are using and include a reference for this result. If you are using a homemade "ball" (paper or foil) research the mass of these substances (e.g. 1 sheet of paper, based on the size of foil sheet you have cut and rolled into a ball; you would need to do a quick calculation) 2) Use a meter stick, or ruler, or cellphone downloaded app ruler. On a wall in your house create markings that are easily visible. Use something NOT PERMANENT that will not damage the wall and can easily be removed (e.g. dark tape or thin piece of sticky note). Ideally mark every 10cm to create a wall mounted measuring device. An allemative way to do this could be constructing ruler measurement markings on sheets of paper then taping the paper to the wall, or hanging them off a closed door, etc. Whatever method you use, make sure this will not cause any damage to your wall so that after the lab is finished you can 100% clean up so there is no evidence or mess left behind. 3) Hold one ball from a constant (measured) position above the floor and record the initial height of the 'ball' from the floor. 4) Drop the ball, and capture its motion (fall) using a cell phone video. This step might be difficult to perform by yourself if you do not have a way to lean or mount your phone to create the recordings. If you have a friend or family member who could help that would be great! (one person to hold and record video footage, the other to hold and drop the object). 5) Record the maximum height of the first bounce in your data table Repeat the experiment for a total of 3 trials for each ball. 7) Repeat steps 3-6 for the remaining 2 balls you have chosen. (in total you are conducting 9 experimental drops) Observations:Type of Mass of Mass of Ball Trial Height of Height of 1st Height of 1st Ball Ball (a) (kg) Release (m) bounce (cm) bounce [m) [name 2 Data Analysis: Type of Mass of Ep at Trial E, at height of Efficiency (%%] Average Ball Ball (kg) original 1st bounce (J) Efficiency of all height () trials (%%) 2 13 2 13Sample Calculation: Show one complete calculation for the object which bounced the highest Mass conversion 1st bounce height conversion Calculation of E, at original (from g to kg) (from cr to m) height Calculation of E, at Calculate average efficiency Calculation of the efficiency of 1st bounce of 3 trial runs the 1st bounce for run 1 Conclusion: Answer the following: List the 3 types of balls used from most to least efficient. Why might the efficiency for each ball be different? Which ball most closely resembled a perfect machine? List 2 sources of error which may have affected your results