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Centripetal Force And Merry-Go-Rounds

The next time you're at a park, watch children playing on a merry-go-round and you'll notice that kids sitting in the center of the merry-go-round don't get as dizzy as those hanging on the edge.

That's because the inner ear helps you keep your balance, and when your inner ear is disturbed by a force such as spinning, you feel dizzy. Kids on the edge of the merry-go-round are experiencing greater force, and therefore are getting dizzier, than those at the center. Here's why.

Dizzy, Dizzy, Dizzy

Physics tells us that objects at rest want to stay at rest, and those in motion want to stay in motion, and when these objects are in motion, they naturally move in a straight line.

To get an object to move in anything other than a straight line, you have to exert force on it. A force is required for an object to move in a circle, as is the case with a merry-go-round. This force is called a centripetal force.

Centripetal Force

Generally speaking, the larger the circle you move in, the greater the centripetal force you experience.

So, the farther you move away from the center of the merry-go-round, the more force the merry-go-round must exert on you to keep you moving in that circle. All this extra force on your inner ear can make you lose your balance and feel quite dizzy.

Try An Experiment

Another way to see centripetal force in action is with an old-fashioned record player. Place a penny near the center of a spinning record, and it will stay in place as it turns.

Put the penny on the edge, however, and it will fly off the record, giving visible proof that the force at the edge of a spinning object is greater than at the center.

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