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# Fun Physics Activities for Kids

Spinning Swings

How on earth do ice skaters spin so fast? The Spinning Swings physics activity will reveal all, with the help of your nearest playground swing set.

This outdoor physics activity teaches about centrifugal force. When a spinning object is compact, it spins incredibly fast. When the object is not compact, the centrifugal force is reduced and the object slows down.

Explore this simple activity with your kids -- and make sure they're prepared to get dizzy.

### What You'll Need:

• Playground swing
• Partner
• Stopwatch

Sit your child on the swing and twist it slowly around and around until the swing is wound up tightly. Have a stopwatch ready; when you let go, time how long it takes for the swing to unwind. Next, try the same thing, but tell your child to stretch her arms and legs out as far as they will go. This puts some of the weight away from the center of mass. Time how long it takes for the swing to unwind.Now instruct your child to pull her arms and legs close into her body. This brings all the weight close to the center. How does this change affect the spinning speed?Next time your child sees skaters on television or in person, point out how they hold their arms when they spin. The closer their arms are to their bodies, the faster they can whirl.

### ABOUT THE CRAFT DESIGNERS

Contributing writers: Maria Birmingham, Karen E. Bledsoe, and Kelly Milner Halls.