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SHPE Foundation SHPE Jr. Chapter Curriculum Hands-on Activity Training. TeachEngineering Hands-on Activity: * Power, Work and the Waterwheel TeachEngineering Digital Library: teachengineering.org. http://commons.wikimedia.org/wiki/File:Waterwheel.jpg.
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SHPE FoundationSHPE Jr. Chapter CurriculumHands-on Activity Training TeachEngineering Hands-on Activity: *Power, Work and the Waterwheel TeachEngineering Digital Library: teachengineering.org http://commons.wikimedia.org/wiki/File:Waterwheel.jpg
SHPE FoundationSHPE Jr. Chapter Curriculum Hands-On Activity Training TeachEngineering Digital Library • The TeachEngineeringdigital library provides free, teacher-tested, standards-based engineering content for K-12 teachers to use in science and math classrooms. • Engineering lessons and activities connect real-world experiences with curricular content already taught in K-12 classrooms. • TeachEngineering'scomprehensive curricula are hands-on, inexpensive, and relevant to children's daily lives. http://www.teachengineering.org
SHPE Foundation SHPE Jr. Chapter Curriculum Hands-On Activity Training General Advice • Be prepared! Do each activity beforehand • Make sure all materials are available • Keep students on task • Follow the time frame • Be flexible • Have Fun!! http://www.teachengineering.org/view_activity.php?url=collection/cub_/activities/cub_energy2/cub_energy2_lesson08_activity2.xml
SHPE Foundation SHPE Jr. Chapter Curriculum Hands-On Activity Training Power, Work and the Waterwheel • Students construct a waterwheel using two-liter bottles, dowel rods and index cards, and calculate the power created and work done by them. • Engineering focus: • Engineering Design Process • Students brainstorm, design, test, collect data, and analyze results for waterwheel blades for the purpose of creating the most efficient waterwheel • Learning objectives: • Make a connection between the concepts of power and work and engineering design. • Work in a design group. • Explore nonlinear functions (ex. power is inversely proportional to time). • Collect data to solve equations and form conclusions. Full Activity on TeachEngineering
SHPE Foundation SHPE Jr. Chapter Curriculum Hands-On Activity Training Power, Work and the Waterwheel • Suggested time: 45 minutes • Suggested group size: 4 students/group • Materials • Each group needs: • 2-liter bottle with caps (drill 3/8-inch holes into the end of the two-liter bottle and the cap.)* • ¼-inch dowel rod (must be longer than the 2-liter bottle) • 15 index cards • 1.2 meters of string • scissors • tape • a 100-200 gram weight (about 1/3 pound) • stopwatch • kilogram or gram scale • pitcher or water jug • funnel • H20 Solutions Worksheet, one per person) *Prepare plastic bottle and bottle cap prior to activity http://www.teachengineering.org/view_activity.php?url=collection/cub_/activities/cub_mechanics/cub_mechanics_lesson05_activity1.xml
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Engineering Connection (Real World Application): • Throughout human history, waterwheels performed many types of mechanical work: saw timber, drive pumps, run farm equipment, trip hammers, grind grains into flour, make iron products and power textile mills. http://itd.idaho.gov/transporter/2011/101411_Trans/101411_StuddedTires.html https://www.cpsc.gov/en/Recalls/2014/Rollerblade-USA-Recalls-Tempest-Inline-Skates/ http://gallery.usgs.gov/tags/mine
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Engineering Connection (Real World Application): • Today, the modern equivalents of waterwheels are the huge turbines of hydroelectric power plants, which generate electricity that we use everyday to perform all types of work: heating, cooling, refrigeration, and the powering of appliances, televisions and entertainment. • Hydropower is a way to produce electricity using a renewable energy source that does not use fossil fuels, pollute or produce greenhouse gases. Such big projects require engineers to consider all the implications of their impact on the surrounding environment. http://commons.wikimedia.org/wiki/File:Kurpsai_Hydroelectric_Station.jpg http://www.nypa.gov/facilities/niagara.htm http://commons.wikimedia.org/wiki/File:POWERHOUSE,_PELTON-FRANCIS_TURBINE_(GENERATOR)_-_Yosemite_Hydroelectric_Power_Plant,_Highways_120_and_140,_Yosemite_Village,_Mariposa_County,_CA_HAER_CAL,22-YOSEM,4-8.tif
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Introduction: • Power and work are important concepts that impact the engineering design of items ranging from racecar engines to elevators to power plants. • High-power cars (high-horsepower) are able to accelerate very quickly and go very fast. • Elevators in skyscrapers require enough power to lift many people quickly, to avoid long elevator waiting lines. • Power plays an integral role in the production of hydroelectricity. • Work is measured in Joules (J) and is defined as a force acting over a distance or: Work = force x distance http://dnr.louisiana.gov/assets/TAD/education/ECEP/diesel/f/f.htm
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Introduction (cont.): • In our activity today, work will be done lifting a weight. • The force term equals the weight and the distance term equals the height lifted. • Power is measured in Watts (W) and is defined by how fast work is done or: Power = Work ÷ time
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Introduction (cont.): • In this activity, you are working for H2O Solutions, an engineering design firm that works mostly with waterwheels and water energy! • Your city wants to use hydropower instead of coal to make energy because they are worried about air pollution. The city has hired you to design an efficient watermill. • The firm (our class) has been split into several engineering teams (student groups). Each engineering team will design and test a slightly different design so that the firm can present the most efficient design to the city. • You will calculate power and work by measuring force, distance and time for your team-built waterwheel.
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Before the Activity: • Gather supplies: Gather materials and make copies of the H20 Solutions Worksheet, one per student. • Prepare materials:Prior to the activity, drill 3/8-inch holes into the end of the two-liter bottle and the cap. This allows the bottles to spin symmetrically and freely about the dowel rod. (If you don't have the hole in the cap, the dowel rod will not spin symmetrically.). http://www.teachengineering.org/view_activity.php?url=collection/cub_/activities/cub_energy2/cub_energy2_lesson08_activity2.xml
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Activity Procedure: • Divide the class into groups of four and pass out the materials. • Remind students of the context of the design challenge (they are engineers working for a firm hired to design an efficient water wheel). They should keep track of their design process using the worksheet. • Instruct students to attach the index cards to the sides of the two-liter bottle to create a waterwheel (open-ended). • Encourage students to brainstorm different ideas of where to place the index cards. • Explain that the water will be supplied from a pitcher through a funnel and the bottle will spin on the dowel rod. http://www.teachengineering.org/view_activity.php?url=collection/cub_/activities/cub_energy2/cub_energy2_lesson08_activity2.xml http://www.teachengineering.org/view_activity.php?url=collection/cub_/activities/cub_housing/cub_housing_lesson04_activity1.xml
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Activity Procedure: • When the students are finished with their design, have them tie the string to the cap end of the bottle so that when the bottle rotates, the string wraps around the bottle neck, pulling up the string. • Measure and tie a weight to the other end of the string. • Make sure to record the mass of the object in kilograms (kg). (For example, 100 grams is 0.1 kg.) Multiply the mass by gravity (~10 m/s2) to calculate your force in Newtons (N). • Have everyone use about the same amount of weight. • Make sure the weights are not too heavy to lift. (For example, 100-200 gram weights work well)
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Activity Procedure: • Test the waterwheels by pouring water through a funnel to achieve an even flow, and timing how long it takes to lift the weight 1 meter (This is your distance). • Perform this test outside or over a sink. • Have two students hold the ends of the dowel rod, one student pour the water and one student time how long it takes and write it down. • Make sure the funnel is only a couple of inches above the waterwheel each time. • Have students calculate the work and power of their waterwheel. Work = force x distance Power = Work ÷ time • Which team had the most power? (Answer: They will all do the same amount of work, but faster wheels will have more power!)
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Assessment: • Pre-Activity Assessment • Brainstorming: In small groups, have students engage in open discussion. Remind students that no idea or suggestion is "silly." All ideas should be respectfully heard. Write down all the groups' ideas on the board to share with the class. "What features make a good waterwheel?" (Possible answers: a lot of fins/index cards to turn the wheel/bottle, each fin/index card holds a large amount of water, symmetry, etc.) • Activity Embedded Assessment • Prediction: Have each student group predict how their waterwheel is going to do and why. Based on their prediction, ask each group if their wheel will do more work or have more power than the other groups. (Answer: They will all do the same amount of work, but faster wheels will have more power.)
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Power, Work and the Waterwheel Assessment (cont.): • Post-Activity Assessment: Question/Answer Have students answer the following question in a short paragraph: • Explain the difference between work and power in your own words. (Answer: Work is a force acting over a distance and is measured in Joules and not dependent on time. Power is work divided by time and is measured in Watts.) Put the following problems on the board (or overhead project) and have students solve them: • Mr. Muscles loads up a bar with 910 Newtons (≈205 lbs) of weight and pushes the bar up over his head 8 times. Each time he lifts the weight .5 meters. How much work did he do? If he does the whole thing in 15 seconds, how much power did it take? (Answer: Work = 3640 Joules. Power = 242.7 Watts. See work, below.) Work = Force x Distance Force = 910 Newtons Distance = .5 meters x 8 = 4 meters Work = 910 Newtons x 4 meters = 3640 Newton•meters = 3640 Joules Power = Work ÷ time = 3640 Joules ÷ 15 sec = 242.7 Joules/sec = 242.7 Watts • How long does it takes a swimmer with a power output of 275 Watts to accomplish 3600 J of work?. If she applied a 650 N force during that time with the same power output, how far did she swim? (Answers: Power = Work / time --> time = Work / Power = 3600 J / 275 Watts = 13.1 seconds. Power = (Force * Distance) / time --> Distance = (Power * time) / Force = (275 Watts * 13.1 seconds) / 650 N = 5.54 meters))
Power, Work and the Waterwheel SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Teaching tips: • Emphasize the science concepts, vocabulary, and engineering connection; reinforce these throughout the activity. • If the weight is too heavy, the waterwheel may not work. If the weight is too light, you won't get an accurate measurement of the waterwheel's power. • Make sure students do not use the dowel rods inappropriately. If testing inside and on tile, the floor may be slippery when wet.
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training Activity Takeaways • Teambuilding skills • Working together on designing, building and testing waterwheel blades • Engineering skills • Engineering Design Process: Students design blades for their water wheel, test and collect data, perform calculations and analyze results. • Encouragement through hands-on learning • Students learn about engineering design, concepts of work and power, and about the use of waterwheels/water turbines. • Motivation through having fun • Introduce the activity as a fun learning experience! http://www.buckeyeaz.gov/index.aspx?nid=163
SHPE FoundationSHPE Jr. Chapter CurriculumHands-On Activity Training TeachEngineeringContact Information • TeachEngineering: http://www.teachengineering.org/ • over 1,300 standards-based engineering lessons and activities • Carleigh Samson, TeachEngineering Editor • firstname.lastname@example.org • 303.492.6950 Questions? http://www.fws.gov/refuge/Stone_Lakes/FAQ.html/