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Wheels in Motion: Bicycles, Roller Skates, & Skateboards

Bicycles, roller skates, and skateboards provide opportunities for learning about the science of motion. The following graphs, excerpted from the series The Science of Wheels from Schottenbauer Publishing, provide data on the motion of wheels.

Discussion Questions
- Which dotted lines show the motion of the pedal? Which dotted lines show the motion of the back wheel?
- How many times does the pedal rotate? How many times does the back wheel rotate?
- What occurs at the end of the graph?
- Does the period of the motion of the back wheel change over the course of the graph? If so, why?

Note: The rotational motion detector has a diameter of 0.8 cm, and the roller skate has a diameter of 6.0325 cm.

Discussion Questions
- How many times does the wheel rotate?
- What is the maximum acceleration of the wheel?
- What is the maximum velocity of the wheel?
- Does the wheel ever roll backwards? How can this be determined?

Discussion Questions
- What is the maximum force exerted to pull the skateboard? The total force?
- What is the work required to pull the skateboard?
- What force would be necessary to pull the skateboard, if no wheels were present?
- What is the average speed of the skateboard in this graph?

Discussion Questions
- Describe the motion of the wheels in words.
- How far do the wheels travel in this graph?
- Estimate the initial velocity of the wheels.
- Estimate the average velocity of the wheels.
- Between 83 and 86 seconds, what is the average acceleration of the wheels?

A free YouTube video, *Understanding the Motion of the Wheel***, **provides graphical analysis of video footage of a bicycle. Analysis of this video is available in the blog article **Understanding Translational and Rotational Motion from a Bicycle Wheel**.

The following books from **Schottenbauer Publishing** contain similar types of graphs and data pertaining to the science of wheels:

*Graphs & Data for Science Lab: Multi-Volume Series*
- The Science of the Wheel
- Volume 1: Roller Skates, Rollerblades, & Halls Carriage
- Volume 2: Bicycle & Skateboard
- Volume 3: Wheels & Axel

- The Science of Exercise Equipment

**Anthologies of 28 Graphs**
- The Science of Transportation

**Additional Information**