I’m just an old hillbilly, so please bear with me! I was using one of my tools and suddenly wanted to convert its RPM (8500) to feet per second (inspired by a question from my son). Since we’re dealing with a rotating disc on a shaft, we’re obviously dealing with linear motion. But after digging around a bit on the internet, I was unable to find a satisfactory formula. If the RPM is 8500, and the diameter is 4.5 inches, how would I first find out the feet per minute, and then finally the feet per second. Thank you so much in advance!

RPM to feet per minuteCalculator

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