rulers + tape +books = Rule Organ

From the MAKE Flickr photo pool

Steven Goodwin shares tips and measurements for making the perfect study hall instrument –

If there’s one piece of science that every kid knows, it’s that twanging a ruler on the edge of the desk makes a noise, and by changing the amount of overhang will change the pitch. Give anyone a new ruler, and the first thing they’ll do is twang it, to see how it sounds. This is an interesting fact of life.
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So, to bring an element of fun back to the proceedings, we can combine these facts to build a very simple ‘rule organ’. By taping thirteen rulers to a nearby desk, each with a different amount of overhang, we have a rudimentary musical (?!?!?!?) instrument. So, how much overhang is necessary, and how do we do it?

Head over to his site for the specifics – Rule Organ

– The Rule Organ on Flickr