## Tuesday, April 14, 2009

### Wind Power Unit Study Day 2

Today we started our study by going through the crash course on the "Wind With Miller" site - www.windpower.org/en/kids/index.htm . This gave us a nice understanding of the parts of a wind turbine. For a multi-lingual element, we switched over to www.windpower.org/de/kids/index.htm , and repeated the crash course in German. Remember, you can also view this site in French or Spanish.

Next we watched Dirty Jobs - Wind Farm Technician. We couldn't find this clip for free, so we opted to pay the \$1.99 at http://www.amazon.com/ to be able to view it instantly. After watching this clip, we asked the question, "Why do wind turbines have to be so tall?" This question is addressed by "Wind With Miller", but we decided to work through the "See the Wind!" lesson we found at http://www.kidwind.org/ . Using a large helium balloon, and a number of streamers we were able to determine that there is a greater amount of wind, and that it is smoother, at a higher elevation.

This exercise added a small math element too, as we converted the metric units of the lesson plan into standard units, and then measured the streamers and the distance between them (as well as the length of the ribbon holding the balloon). However, a word to the wise - if you have smaller children, save this exercise to last. It can be very difficult to get any more science done once a three foot helium balloon enters the house!

Our balloon popped quickly, and so we were able to move on to making an anemometer to study wind speed. As we learned from "Wind With Miller", if the wind speed is too great, the wind turbines must shut down in order to keep from flying apart. They have anemometers on top of the nacelles to keep track of the wind speed.

For this exercise, we used a worksheet from www.oregonctc.org/solar/maketake.pdf . It gives simple instructions for turning a few household items into a crude anemometer, which along with a watch with a second hand, can be used to keep track of wind speed outside your home.

Finally, we made a wind sock, following the instructions on the "Wind With Miller" site. When combined with a compass (and some actual wind), this will help us track wind direction throughout the day.

Tomorrow, we hope to continue our study of the components of a wind turbine. I had planned to cram in a little more today, but silly me, I forget to allow time for mourning the loss of a popped balloon. Is there a special funeral service for a beloved balloon?

It's great to be a homeschooler!