LEARN NC

3 Designing for speed and distance

By Roxanne Moses

Provided by Kenan Fellows Program.

blue and white car

Students must choose to design their self-propelled cars for safety or distance.

In this lesson, students will learn about factors engineers must balance when designing a car. Students will find that not only must engineers consider the actual car design, but also road design and fuel limitations. Students will apply some of their new knowledge as they continue to work on their own car designs.

Learning outcomes

Students will:

  • Learn about technological design factors that influence the speed and distance capabilities of a car
  • Learn how energy is used in a car and about the limitations of different types of fuels
  • Gain experience and comfort in public speaking
  • Work together as a team on their car designs

Teacher planning

Time required

One class period

Materials needed

Materials for the construction of the car should be available. This list is repeated from the first lesson in this unit.

  • springs
  • rubber bands
  • carbon dioxide
  • water bottles
  • balsa wood
  • wheels
  • axles
  • eye screws
  • thin braided rope
  • coping saw
  • glue
  • sanding block
  • measuring tape

Student handouts

Group two expert interview: Energy and fuel
Document by the author
Open as PDF (17 KB, 3 pages; also available as Microsoft Word document)
Quiz: Designing cars for speed and distance
Document by the author
Open as PDF (13 KB, 1 page; also available as Microsoft Word document)

Activities

  1. Explain to students that auto manufacturers design vehicles for different performance characteristics such as safety, economy, acceleration, and endurance. Remind the groups that they will be designing their self-propelled car to compete for either speed or distance. As a group, they will need to decide which feature is most important to them and why.
  2. Review terms listed in the Critical Vocabulary. If you think it will be helpful, show diagrams of the internal workings of a car as you review the vocabulary.
  3. Group Two will present the Energy and Fuel expert interview.
  4. Discuss the information presented in the expert interview. Ask students to share information they found interesting or surprising. Students will likely have a lot to say about fuel and alternative forms of energy. Make sure to keep the discussion focused and brief but be sure to answer any questions or elaborate on concepts that are unclear.
  5. Lead a conversation about design factors that influence speed and distance capabilities of cars. Some of these factors include:
    • aerodynamics
    • weight
    • engine type
    • fuel/energy source
    • tires
    • friction
  6. Students should spend the remainder of the class working on their car designs. Encourage students to use information from class discussions and the expert interviews in their work.
  7. During the last five to ten minutes of class have students complete the short quiz.

Assessment

Students will take a very short quiz at the end of class. Check answers for understanding.

Critical vocabulary

air charge
the temperature of the air sucked into the carburetor or fuel injection system
carburetor
a device used in internal-combustion engines to produce an explosive mixture of vaporized fuel and air
combustion
a chemical reaction that occurs between a fuel and an oxidizing agent that produces energy
drive shaft
a rotating shaft that transmits mechanical power from a motor or an engine to a point or region of application
drive train
the components of an automotive vehicle that connect the transmission with the driving axles and include the universal joint and drive shaft
fuel injection system
mechanical system to inject atomized fuel directly into the cylinders of an internal-combustion engine; avoids the need for a carburetor
kinetic energy
the energy possessed by a body because of its motion, equal to one half the mass of the body times the square of its speed
supercharger
a blower or compressor, usually driven by the engine, for supplying air under high pressure to the cylinders of an internal-combustion engine
turbocharger
a centrifugal blower driven by exhaust gas turbines and used to supercharge an engine

North Carolina curriculum alignment

Science (2005)

Grade 8

  • Goal 1: The learner will design and conduct investigations to demonstrate an understanding of scientific inquiry.
    • Objective 1.01: Identify and create questions and hypotheses that can be answered through scientific investigations.
    • Objective 1.07: Prepare models and/or computer simulations to:
      • Test hypotheses.
      • Evaluate how data fit.
    • Objective 1.10: Analyze and evaluate information from a scientifically literate viewpoint by reading, hearing, and/or viewing:
      • Scientific text.
      • Articles.
      • Events in the popular press.
  • Goal 2: The learner will demonstrate an understanding of technological design.
    • Objective 2.02: Use information systems to:
      • Identify scientific needs, human needs, or problems that are subject to technological solution.
      • Locate resources to obtain and test ideas.
    • Objective 2.03: Evaluate technological designs for:
      • Application of scientific principles.
      • Risks and benefits.
      • Constraints of design.
      • Consistent testing protocols.