Calculating Length of Strand of Gold in "Rumpelstiltskin"

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In "Rumpelstiltskin," the miller's daughter spins straw into gold on a wheel rotating at 7.5 m/s, completing one revolution every 0.5 seconds. To find the length of a strand of gold for one complete turn, the speed of the wheel's perimeter is crucial. By multiplying the speed (7.5 m/s) by the time for one revolution (0.5 s), the length of the strand can be calculated. This results in a straightforward application of dimensional analysis and geometry. Understanding these concepts is key to solving the problem effectively.
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In “Rumpelstiltskin,” the miller’s daughter is spinning straw into gold on a spinning wheel that turns at a speed of 7.5 m/s, making one revolution every 0.50 s. How long is a strand of gold that makes one complete turn around the wheel?

I know I am supposed to be telling what I know, but frankly I have no idea how to do this. I do no know the equation. I also do not understand how the wheel spins at one speed; isn't it supposed to spin at different speeds in different parts??

HELP!
 
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You have to assume that the 7.5m/s refers to the speed of the perimeter of the wheel. Knowing that the perimeter of the wheel goes at 7.5m/s and that it makes one full revolution in 0.5 seconds, does that help? Applying only simple geometry now ^^
 
have you learned dimensional analysis?

multiplying 7.5 m by .5 s gives you the number of meters in one revolution, which is what you're looking for.
 
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