1. Windmill lab
2017

2. Goals
Students will design a controlled experiment (unlike the Bubble Lab) to learn how to maximize the power of a windmill.
To learn about variables
Students will alter one variable in a windmill setup to see how it will affect its power.
To learn about controls
Students will keep all other variables constant in order to be certain that the independent variable is causing a change in its power.
To learn about Energy and Power
Students will learn to measure the energy and power output of a windmill (relationship between energy and power).
Students will attempt to maximize the power output of a windmill.

3. Orientation
Turbines can be categorized into two overarching classes based on the orientation of the rotor
Vertical Axis Horizontal Axis
Turbine can spin on a vertical axis or a horizontal axis

5. http://www. mywindpowersystem

6. Constants

8. Control Group set up
Angle: 25 degrees Length: 12 inches # of blades: 4 Shape: 3x12 inch rectangle Distance from fan: 50 cm Fan speed: high

9. Whales and Turbines Why are new blades needed?
What do you think Dr. Fish’s hypothesis was?
How was his hypothesis tested?
What was tested? IDV and DV
What things were kept constant in the experiment?
What were the results?
What are the next steps?

10. Variables – what factors could affect the power of a windmill?

11. Dependent vs. Independent
Independent variable: __________________ Dependent variable: ____________________

12. Variables – what factors could affect the power of a windmill?
Angle of Blade
Length of Blade
Number of Blades
Width of Blade
Thickness of Blade
Shape of Blade
Composition of the blade
Distance from fan

13. Data
qualitative or quantitative?

14. Hypothesis
If then because .

15. Procedure
Be as SPECIFIC and CLEAR as possible when you write the plan.
Draw blade shapes you plan to test
What will you do first? Second? Etc.
Who will perform which tasks? What are the tasks?
Include instructions on EVERY constant (Items in your variables table)

17. To do / today
Today
Finish Collecting Control Data (for last trial, record most washers your control group can lift, record in greatest mass lifted column)
Choose IDV/ Clear procedures with Mr. Mega
Collect Data for IDV
With 5 washers as your constant, run time trials for IDV
For each change in your IDV (AND THEIR SHOULD BE 5) record the total number of washers it could lift in greatest mass lifted column
Clean up after yourselves
Homework:
Fill out the remainder of your data tables (energy and power); Prepare to relay your data to the class; Write a semi formal lab report by following the lab sheet instructions and including all sections outlined.

18. Time to lift washers (Sec)
Example Data Table 1
Trial: Control Group
Mass of washers lifted
(grams)
(kg)
Height
(m)
Time to lift washers (Sec)
Energy
(J)
Power
(W)
inches
0.5 m
inches
inches
4. 11 inches

19. Time to lift washers (Sec)
Example Data Table 2
Trial: Describe IDV
Mass of washers lifted
(grams)
(kg)
Height
(m)
Time to lift washers (Sec)
Energy
(J)
Power
(W)
1.______________
Control Group
0.5 m
2..
3..
4..

20. Things to consider..
5 trials must be the standard setup (Control Group).
If the cup isn’t lifted to the top, it doesn’t count. Remove some washers from the cup.
Check the angle of the blades every trial.
Check the distance of the fan every trial
Don’t forget to time how long it takes to lift the washers.
Make sure each person knows what their job is.
Every individual must have their own data table.
DIVIDE UP THE LABOR AND WORK QUICKLY OR YOU WILL NOT FINISH ON TIME.

21. Symposium The goal is for you to… share your results with other groups
and to allow you to hear what other groups discovered during their experiments.
Help yourself/peers learn about the strongest windmill design.
Link to real life:
Engineering firms and research universities like CU host symposiums periodically to share new information with other people in their field.
“No man is an island.” – John Donne
“If I have seen further it is by standing on the shoulders of giants.” – Sir Isaac Newton

22. Symposium
Design
# of Washers Lifted
Seconds
Power
1..
2..
3..
Design
Max # of washers lifted
Seconds
Power
What were the challenges you encountered when testing the windmills?
How did you overcome them ?
What advice you can offer to fellow students when creating a windmill?

23. Challenge Day Activities: Windmill challenge (25-30 minutes)
Review for quiz next class.
Discuss homework (podcast)
Goal:
Make the strongest windmill! MOST POWER AND MOST ENERGY (Two different challenges)
To utilize the information we gained from controlled experiments.