Team 1, 2012 Lessons/Activities:2. Plastic Water Bottles - What’s the Best Shape? Larry Braile, Dept. of Earth and Atmospheric Sciences

Jenny Daugherty, Dept. of Technology, Leadership and InnovationHelen McNally, Dept. of Electrical and Computer Engineering

TechnologyInez Hua, Dept. of Civil EngineeringJenniffer Dickensheets, 5th Grade Teacher, Sunnyside Middle

SchoolPam Stamm, 5th Grade Teacher, Taylor Intermediate SchoolMelissa Colonis, 7th Grade Math Teacher, Tecumseh Junior High

SchoolConstance Harris, Grad Student, College of Education

Plastic Water Bottles – What’s the Best Shape?

Lesson Objectives: Students will be able to:Measure the volume and surface area of objectsDetermine surface area to volume ratiosOptimize the surface area to volume ratio (to reduce the amount of plastic used to make the bottles).

Plastic Water Bottles – What’s the Best Shape?

Indiana Science Standards: 5.5.4 Find the surface area and volume of rectangular solids using appropriate units.5.4.2 Investigate the purpose of prototypes and models when designing a solution to a problem and how limitations in cost and design features might affect their construction.The Design Process

K-8 Science Process Standard: The Design ProcessAs citizens of the constructed world, students will participate in the design process. Students will learn to use materials and tools safely and employ the basic principles of the engineering design process in order to find solutions to problems. Identify a need or problem to be solved. Brainstorm potential solutions. Select a solution to the need or problem. Select the most appropriate materials to develop a solution that will meet the need. Create the solution through a prototype.

Plastic Water Bottles – What’s the Best Shape?

Americans use an estimated 29 billion plastic water bottles* per year. Manufacturing these bottles uses about 17 million barrels of crude oil (equivalent to almost one day’s use of crude for the U.S.), as well as substantial water and energy consumed in the manufacturing process. It is estimated that only about one out of six plastic water bottles is recycled, instead they become part of landfills and oceans and they do not degrade easily.* A typical school classroom, filled floor to ceiling, could hold about 300,000 one-liter plastic bottles. So, it would take about 100,000 classrooms to hold all of the plastic bottles used in the United States in just one year.

Plastic Water Bottles – What’s the Best Shape?

Americans use an estimated 29 billion plastic water bottles* per year. Manufacturing these bottles uses about 17 million barrels of crude oil (equivalent to almost one day’s use of crude for the U.S.), as well as substantial water and energy consumed in the manufacturing process. It is estimated that only about one out of six plastic water bottles is recycled, instead they become part of landfills and oceans and they do not degrade easily.* A typical school classroom, filled floor to ceiling, could hold about 300,000 one-liter plastic bottles. So, it would take about 100,000 classrooms to hold all of the plastic bottles used in the United States in just one year.

http://www.youtube.com/watch?v=y5y1W5xduiE

http://kids.nationalgeographic.com/kids/stories/spacescience/water-bottle-pollution/

Plastic Water Bottles – What’s the Best Shape?

Several manufacturers are trying to reduce the plastic used in water bottles. Thus far, it appears that none of these manufacturers is addressing the optimum shape for bottles of standard volumes (500 mL, 1000 mL, etc.). The design task is to use the ratio of surface area to volume to optimize the shape and size (radius, height, side length) of bottles to minimize plastic used. The students will gain significant practice with calculations (surface area and volume of standard shapes) and a relatively simple optimization problem. A follow-up question will be to brainstorm other solutions or strategies to address the issue of plastic bottles.

Other containers – juice boxes, milk cartons, etc.

r h r/h S S/V

1.5 70.736 0.02121 680.8 1.3616

2.5 25.465 0.09818 439.27 0.87854

3.5 12.992 0.26939 362.68 0.72536

4.5 7.8595 0.57256 349.46 0.69892

5.5 5.2613 1.0454 371.88 0.74376

6.5 3.767 1.7255 419.31 0.83862

“Thin” Cylinder

“Regular” Cylinder“Wide” Cylinder

Best r/h (although a little thinner or wider

would be OK)

An optimization problem

Skewer (2) 6.5 cm sharp end, 6.5 cm cut end (Earth)

Skewer (2) 8 cm each base (blue styrofoam)

Straw (2) 6.5 cm, 8 cm