String unwound from wheel 20 cm in diameter at 75 cm/s

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A string wound on the rim of a wheel 20 cm in diameter is pulled out at a rate of 75 cm/s. Through how many revolutions will the wheel have turned by the time that 9.0m of string has been unwound? Also how long did it take?

I really need help with this. If you post, please show all work so I can learn how to do this type of problem.
 

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joecocobo, welcome to PF.

You'll have to follow the posting template and show your attempt at working on the problem before help/hints/guidance can be offered.
 

Homework Statement


A string wound on the rim of a wheel 20 cm in diameter is pulled out at a rate of 75 cm/s. Through how many revolutions will the wheel have turned by the time that 9.0m of string has been unwound? Also how long did it take?


Homework Equations


I don't know any equations to use


The Attempt at a Solution


I honestly don't know where to start, to even make an attempt
 
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You may be overthinking it. For starters, separate the question into its two components. They are not related.1] A 9.0m string is wound on the rim of a wheel 20 cm in diameter. How many times is the string wrapped around the wheel?
Do you know the relationship between the diameter of a circle and its circumference?

2] How long will a point on the string take, moving at 75cm/s, to travel 9.0m?
Do you know how to calculate time, given a distance and a velocity?
 
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