Spinning Your Wheels
Why do tires appear to spin backwards in some car commercials?
Students will
- Convert between different units of speed (miles per hour, inches per second, and inches per frame of video)
- Calculate the circumference of a tire, given its diameter
- Convert between speed of a car and rotational speed of its wheels
- Determine whether a wheel will look like its spinning forwards or backwards, based on its rotational speed
- Predict how the tire of an accelerating car will appear to spin on film
Before you begin
Students will need to perform a lot of unit conversion in this lesson, so some previous experience will be helpful (e.g. the ability to convert a speed in miles per hour to feet per second). Students should also know the formula for the circumference, C, of a circle of radius r (C = 2πr).Common Core Standards
Content Standards
Mathematical Practices
Downloads
Additional Materials
- Colored pencils (optional)
Shoutouts
Infinity
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