Energy systems
Invent-a-Wheel
4. Surfaces and Friction
Overview
Students begin with ramps that are at the height that would make the sled move in Lesson 3. They vary the surface of the slide. What effects do these different surfaces have?
Advance Preparation
Materials
Procedure
Setting up six surfaces: Set up or help students set up six ramps per group, adjusted to the minimum height to make the sled go down (discovered in Lesson 3.) Attach a different surface to each ramp, except one, which should be left bare. The six ramps should have the following surfaces: aluminum foil, felt, sand paper, wax paper (crumpled), card stock, and plain cardboard
2.
Predicting what each surface will do: Ask students to predict:
3.
Doing the experiment and recording data: Ask students to test each ramp, and record the results on the worksheet. Students can identify each surface by writing its name, or by gluing a small sample of each one onto the worksheet.
4.
Class chart: Create a chart with the class that lists all the surfaces the students tried. Beside each surface record the lowest height that the slider was able to slide on.
5.
Outcomes
