Thursday, April 16, 2009

Wind Power Unit Study - Day 4

Today we powered up our model wind turbine by adding a real electric generator! Never mind that our wind turbine is currently a pinwheel stuck on the end of a ruler, and our generator is a small DC variety we saved out of one of those battery science kits - power is power. We used a hair dryer for wind, and a volt meter to test the amount of power being generated. To copy this experiment, you need -

  • A sturdy ruler - for the nacelle.

  • A small DC generator.

  • Some tape - we used electrical tape.

  • Two insulated copper wires with alligator clips attached to one end.

  • A cork or the eraser out of a new pencil for the shaft.

  • Some type of rotor - we used a paper pinwheel, the propeller from a toy plane, and some addition flashcards on half-straightened paperclips.

  • A voltmeter.

We taped the generator to the end of the ruler, attached our wires off the back end, and then clipped the alligator clips to the voltmeter. Next we attached our rotor to the shaft (we stuck the thumbtack of the pinwheel into the eraser), and then attached the shaft onto the rod of the generator.

We switched out our rotors a few times to see which would give us the most power (the little plane propeller worked the best for us). None of our rotors allowed us to produce enough power to light even a tiny light bulb. Even so, we were able to graph our results, and we learned the importance of a yaw mechanism to keep the rotors turned into the wind. Our power readings dropped off quickly when our rotors were not meeting the wind head on.

Normally, this would have been the point to give the children a variety of materials to try making and testing their own rotor designs. Today, however, the Disney Handy Manny DVD I had ordered weeks ago from a partner library, finally showed up. In one of those funny twists, it was the "Go Green Edition", so we had to stop and watch it, and have a snack of green pudding(you know, living la vida verde!)

It might not be what the environmentalist have in mind, but I can assure you, after a snack of pistachio pudding, my kitchen is looking pretty green.

It's great to be a homeschooler!

No comments: