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Overview

In this lesson students will change the properties of a material by applying heat, and will see how the heat can rearrange atoms and change the material's physical shape. The shape's change generates force they can harness to run a simple machine, a lever.

Content Objectives

1. Students will create a simple machine (lever).
2. Students will understand what an actuator is and how it works.
3. Students will analyze examples of simple levers.
4. Students will analyze the performance of a lever by adjusting some variables associated with a lever.
5. Students will determine the variables that affect the performance of a lever and how each affects the lever’s performance.

Grade Level: 9-12

Suggested Time

• Approximately 90 minutes

Process Objectives

1. Students will evaluate the lever’s performance and make necessary changes to increase the performance.

Assessment Strategies

1. Completion of the “Levers, Actuators, and Exciting Materials” lab.

Media Resources

1. Levers, Actuators, and Exciting Materials Lab PDF Document

2. Levers, Actuators, and Exciting Materials Teacher's Guide PDF Document

3. Moving Atoms QuickTime Video (3 minutes 07 seconds)

Materials

• A piece of nitinol “muscle wire” about 18 cm long
• A spool of small gauge, uncoated copper wire (22 gauge or smaller)
• A package of n-size model train track connectors. You will want to cut them into their 1 cm long components. See the pictures of the connections for more information
• A 9V battery and connector
• A simple switch
• Two staples
• A paper fastener
• A few push pins
• A large piece of foamcore board
• Needle-nosed pliers
• Duct tape
• Scissors or a pen knife
• Ball bearing (optional)

Procedure

1. Teacher should start a discussion about simple machines with a focus on how they make everyday life easier.
2. Teacher should ask the students to brainstorm a short list of examples of levers.
3. After a short discussion of the student-generated list, the teacher should have students read the background information on the

   Levers, Actuators, and Exciting Materials Lab PDF Document

   .
4. The teacher should ask the students to think of more complex products that might include levers. Are there any applications of a lever that involve more complex processes such as gears, fire, electricity, etc.?
5. If any students have not already seen it, the teacher should allow the students to watch the clip: Moving Atoms QuickTime Video (3 minutes 07 seconds)
6. Teacher should discuss an actuator and its applications.
7. Teacher can inform the students that they will be creating a lever using an actuator and electricity.
8. Students should follow the instructions on the

   Levers, Actuators, and Exciting Materials Lab PDF Document

   and complete the questions.

Extension

1. Students can complete the “Extension” section of the lab by adding a third lever, or adding a ball bearing to the lever to observe its ability to do work.