If you swing a yo-yo in a circle, the string has centripetal tension. That’s the force keeping the yo-yo from flying into your neighbor’s face. The formula is T = mv²/r, where m is mass, v is speed, and r is the circle’s radius. Faster swing = more tension. Too much tension? String snaps. Yo-yo goes interstellar.
This is why amusement park rides have massive cables. They need tension to keep you from becoming a projectile. Next time you’re on a swing ride, think about the math keeping you safe. Or don’t—just scream.
