Spinning wheel

1. Nov 21, 2005

matiishere

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!!!!!!!!!!

2. Nov 21, 2005

mezarashi

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 ^^

3. Nov 21, 2005

jalapenojam

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.