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Q & A: Why do 'perpetual motion' toys need batteries?

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Most recent answer: 12/09/2014
Q:
Why does a kinetic art perpetual motion toy need a battery? what is the battery's function?
- Jennifer Gilchrist (age 48)
Yellow Springs, Ohio, U.S.A.
A:

Hello Jennifer ,

It's because 'perpetual motion' toys aren't really perpetual.  There always exists some friction that will drain the kinetic energy of the moving parts.  The toy just 'runs out of gas'.  You need to restore this energy with a battery.

If you type perpetual motion into the P-Van search box you find lots of information about this subject.

LeeH

p.s. Spoiler alert: The key piece of information you'll find is that there isn't any such thing. /mw


(published on 12/09/2014)

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