Lesson Plans

Return to Lesson Plan Index
Printer Friendly Version

Energy Cars and Polymers: Reducing Frictional Forces

Grades: 9
Author: Vitaliy Baranovskiy
Source: Original - This material is based upon work supported by the National Science Foundation under Grant No. EEC- 1542358.

Abstract

Students will be working in pairs to design and build energy car that meets specific requirements by using knowledge of polymer chemistry, and laws of physics. The goal of the project is to build a car that would go maximum distance when launched by rubber band, therefore, students will have to apply knowledge about motion, friction, and engineering principles to achieve best results. Energy car must be build from wood platform, and wheels from thermoplastic. During this lesson, students will learn about thermoplastics (polymers), friction (sliding, rolling, fluid, static), and motion (speed, acceleration, velocity).

Objectives

What should students know as a result of this lesson?

Students will be able to name four different types of friction.
Students will be able to define polymers and name practical uses of polymers.

What should the students be able to do as a result of this lesson?

Students will be able to use engineering principles to evaluate and increase performance of energy car.

Materials

Wood platform, (2 inches x 4 inches), HEA-500 thermoplastic, nails, lubricants, sand paper, glue, rubber bands, hot water (80 degrees C), balance, ruler/meter.

Procedures

Engagement

Introduce students to polymers by asking students questions: What are polymers? Where are they used? And name few uses of polymers. Following discussion about polymers, demonstrate polymer "thermoplastic HEA-500" and explain how this would be used in making wheels for the energy car.

Exploration

Introduce students to entire project and ask them to work in their groups in designing and building wheels for energy car from thermoplastic HEA-500. Afterwards, ask students to build energy car by following appropriate guidelines.

Explanation

After students build energy car, ask students what can they do to maximize distance travelled by the car. Introduce the idea of friction, and ask students to evaluate and optimize their energy car to reduce frictional forces.

Elaboration

Let students test their energy car and see which cars will travel greatest distance. Following testing for the energy cars, review idea of polymers and friction and give students short assessment.

Prerequisites

Knowledge of motion, speed, velocity, acceleration.

Best Teaching Practices

In order to complete this lesson plan make sure students are able to work on energy cars and wheels for at least 3 hours but no more than 5 hours. Allow students to observe other groups for ideas and suggestions.

Alignment with Standards

NGSS Standards:

RST.11-12.7 Integrate and evaluate multiple sources of information presented in diverse formats and media (e.g., quantitative data, video, multimedia) in order to address a question or solve a problem. (HS-PS2-1)

Ohio Standards:

Motion:

Introduction to one-dimensional vectors
Displacement, velocity (constant, average and instantaneous) and acceleration
Interpreting position vs. time and velocity vs. time graphs

Content Knowledge

Motion, speed, velocity, acceleration, polymer, friction, rolling friction, sliding friction, fluid friction, static friction.

Safety

Follow laboratory safety rules including wearing safety goggles, do not touch hot water what would be used to melt thermoplastic.

Applications

Students will be able to experience how polymers are used in real world.

Assessment

Students should be able to build energy car and optimize it to reduce frictional forces on it. After project assess students knowledge on polymers and different types of friction.

Other Considerations

Grouping Suggestions: Let students work in pairs and allow them to choose their own partners.

Pacing/Suggested Time: 1 day for introduction; 3 days for building energy car; 1 day for evaluation and testing

Requirements for Energy Car

The mass of the car cannot exceed 500 grams
Each team can use up to 50 grams of thermoplastic to build wheels for the energy car (12.5 grams per wheel)
Car must have 4 wheels that touch the ground and freely rotate.
Making wheels for energy car: Students will be using HEA-500 thermoplastic to make wheels for the energy car. HEA-500 thermoplastic comes in solid pallets that first must be heading in hot water. Once heated, thermoplastic will melt and students will be able to shape it into a circular wheel. Thermoplastic will solidify in about 1-2 minutes, therefore, it is important to mold wheels right after removing thermoplastic from hot water. Groups will be given 50 grams of thermoplastic, thus, each wheel should be 12.5 grams.
Testing Energy Cars: All cars must be launched into motion using same techniques and force. Therefore, teacher must ensure that during testing stage all energy cars are launched into motion with same force (using same rubber band).

Evaluation

Evaluation Rubric:

Car meets mass requirements (4 pts):_________________
Car meets wheel requirements (4pts):_________________
All four wheels touch the ground freely rotate (4 pts):__________________
Car has at least one technique to minimize some friction force (4 pts):___________________
Creativity (4 pts):____________________

Safety Disclaimer