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Reversal

Luke helped decorate the Christmas tree today---he's home sick, but you don't always feel like lying on the couch if you are sick. 

He decided that the glass ornaments should be put on the lower branches, because, "If the tree falls, they are less likely to break."  It wasn't too long ago that putting the glass ornaments on the lower branches made it more likely that they would break.

He also helped check every light on a string to find the ones that were burnt out so that the string would light again.  In the course of going through the lights we found some that made the string blink.  He wondered how it worked---after all, the bitty bulb wasn't big enough to have a computer controller in it.  When he looked inside at the bulb he saw a thick strip near the filament.  "A bi-metalic strip! That's brilliant!"  He was impressed by the genius of a bi-metalic strip for the next few hours.  I wonder if that's how they really work...

Comments

Michael said…
Yes, it is a switch made from a bimetallic strip.

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