Angular Quantities: Calculating Revolutions

AI Thread Summary
To calculate the number of revolutions a tire makes, divide the distance traveled by the circumference of the tire. The circumference is determined by multiplying the radius by 2 pi. A wheel's distance traveled can be expressed as the product of its circumference and the number of rotations. Angular displacement can be related to linear displacement using trigonometry. Understanding these relationships clarifies the calculations for angular quantities.
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Hey, I ran into a few things about angular quantites and am a little confused on finding the number of revolutions something such as a tire would make. Would the distance traveled divided by a circumference of a circle equal the number of revolutions? I was finding that there are equations that show an angular displacement divided by 2 pi, so if a radius is known is it useful or not? I couldn't decide whether to divide anything by a radius of Circumference or just 2 pi. Also, with angular displacement would it work to use just displacement in linear distances? Thanks!
 
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To find the circumference, you times the radius by 2 pi.

Finding the distance a wheel covers is merely the circumference times by the number of revolutions. So a wheel with a radius of 30cm rotating 2.5 times will travel 471cm. Ok?

So the distance traveled by a wheel will equal the circumference * number of rotations.

You can relate angular displacement to linear displacement using trigenometry, are you familiar with this?
 
Thanks so much, that really helps! :)
 
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