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Name: ______Group members: ______Core: ______
Roller Coaster Lab
Introduction
Design a roller coaster using pipe insulation, masking tape, a marble, a lab stool/chair/countertop, and your table. The roller coaster should begin near the top of the stool/chair and end on the floor. After your roller coaster has been built and tested, make the following measurements/calculations.
Measurements and Calculations
Mass of marble: ______
Design I
Gravitational Potential Energy
Choose h = 0 to be at floor level, which means the floor has a potential of zero.
· Measure the height from which the marble is released (mark it): ______
· Calculate PE = mgh =
Kinetic Energy
Measure the speed at which the marble leaves the roller coaster.
· Mark off a distance on a meter stick to measure the speed of the marble as it leaves the roller coaster. d = ______
· Release the marble from the height that you measured and time how long it takes the marble to travel the marked distance, d, on the floor. Make three measurements and take an average.
Ø time 1: ______
Ø time 2: ______
Ø time 3: ______
Ø average time: ______
· Calculate the speed at which the marble leaves the roller coaster (use the average time in your calculation): v = d/t =
· Calculate KE = ½ mv2 =
Roller Coaster Lab (continued)
Design, build, and test a second roller coaster. Try something new this time, and make the same measurements/calculations as before.
Measurements and Calculations
Mass of marble: ______
Design II
Gravitational Potential Energy
Choose h = 0 to be at floor level, which means the floor has a potential of zero.
· Measure the height from which the marble is released (mark it): ______
· Calculate PE = mgh =
Kinetic Energy
Measure the speed at which the marble leaves the roller coaster.
· Mark off a distance on a meter stick to measure the speed of the marble as it leaves the roller coaster. d = ______
· Release the marble from the height that you measured and time how long it takes the marble to travel the marked distance, d, on the floor. Make three measurements and take an average.
Ø time 1: ______
Ø time 2: ______
Ø time 3: ______
Ø average time: ______
· Calculate the speed at which the marble leaves the roller coaster (use the average time in your calculation): v = d/t =
· Calculate KE = ½ mv2 =
Analysis Questions
1. In the absence of friction and other sources of energy loss, how should the values for the marble’s PE at the beginning and KE at the end compare?
2. In realistic analyses, frictional effects and energy loss must be accounted for. Was there a big difference in the PE calculated and the KE calculated for design I? Explain why or why not. Was the difference bigger or smaller than you expected?
3. For design I, calculate the energy lost as the marble went through the roller coaster. (Hint: PE = KE + energy lost)
4. Describe as many possibilities as you can think of for energy to be lost as the marble makes its way through the roller coaster.
5. For design I, calculate the percentage of available energy lost (energy lost/PE x 100) during the ride.
6. Giving specific examples that relate to your roller coaster (design I), what were some of the ways that you observed energy being lost throughout the marble’s journey?
7. In what ways do you think the roller coasters could be modified in general to be more efficient?
8. Was there a big difference in the PE calculated and KE calculated for design II? Explain why or why not. Was the difference bigger or smaller than you expected?
9. For design II, calculate the energy lost during the ride. (Hint: PE = KE + energy lost)
10. For design II, calculate the percentage of available energy lost (energy lost/PE x 100) during the ride.
11. Which design provided for a more efficient transfer of energy?
12. Give several reasons that could explain the answer to the previous question.