Applying Engineering Principles in High School Physics By Catherine Molloseau, Ph.D. Oregon Episcopal School October 15, 2011

“The major goal of engineering is to solve problems that arise from a specific human need or desire. To do this, engineers rely on their knowledge of science and mathematics as well as their understanding of the engineering design process.” -from A Framework for K-12 Science Education Standards, prepublication copy, National Academy of Sciences 2011

Overview of Presentation Method for introducing engineering principles in the classroom Introduction of sample engineering design lesson plan Review common issues and considerations for students and teachers Other engineering lesson plans to consider

Engineering Design Process

The Solar Car Project Step One: Define the Problem Objective: students are given 2-3 weeks to design, build and test a solar car on a 10 meter outdoor track using skills developed throughout the year while gaining a better understanding of alternative renewable sources of energy Physics topics: mechanics, energy, waves, electricity and magnetism Constraints: Mass of car: < 200 g Volume: length < 10 in, height < 5 in, width < 5in Power supply: must come from provided 3.0 V solar panel Cost: $6 for kit of parts (provided) + $10 additional

Kit of Parts Each kit contains A piece of balsa wood 3.0 V solar panel DC motor 4 plastic wheels 4 gears 2 axles 1 straw 4 aluminum washers

The Solar Car Project Step Two: Brainstorm Students are put in groups of two and are given 1-2 class periods to investigate the components of the kit Students are encouraged to draw upon their physics knowledge in deciding on a design Preliminary sketches are made of the possible car designs either by hand or using a program such as Google Sketch up

The Solar Car Project Step 3: Design Student Sample of Car Design Using Google Sketch Up (2008)

The Solar Car Project Step 4: Build Students are given 2-3 50 minute class periods to construct the car Hot glue is often used to attach parts Students learn how to solder wires between the motor and solar panel An Exacto knife can be used to cut the balsa wood Students are encouraged to decorate their cars to make them unique

The Solar Car Project Step 5: Test Students do preliminary testing of cars Common things students observe are The car’s path (is it linear?) The acceleration/top speed of the car Durability 2008

The Solar Car Project Step 6: Share for Feedback While students test their vehicle, they discuss any issues in order to make improvements The teacher can also observe and question students about the design of the car After all testing is finished, students write a 4-5 page technical paper that includes the method used, technical drawing of the car, results, and a discussion of the car’s overall performance

The Solar Car Project Step 7: Modify to Improve After preliminary testing, students return to lab to make improvements Typical issues are Solar panel angle Motor attachment Gear ratio Mass Car veers in one direction or another 2008

The Solar Car Project Final Step: End Product The race day is chosen so as to maximize the possibility for sun The teacher locates a level surface (parking lot, track, walkway) and measures out 30 meters (oriented so the race takes place from east to west) Students race their cars 5-7 times, and the teacher records the places of each finish Students also record the time of each run for at least 3 races

The Solar Car Project Final Step: End Product Sample cars (2011) Race Day (2008)

Other considerations/common issues Plan ahead for race day (Oregon weather even in May is often cloudy) Specify the location of the race track and direction of travel (east to west, north to south, etc.) Hot glue guns are a must!! Give students at least 4 class days to work on the project (rather than requiring it to all be done outside of class) Make it fun! Give a prize to the top 3 finishers from each class (or have a race off among different classes)

Other Lessons that Utilize the Engineering Design Process Golf ball boat (1 class period) Wind turbine (2 class periods) Bunny Bungee (1-2 class periods) Ornament drop survival (1 class period) Maximizing speaker timing for surround sound (2 class periods)