10.31.11 Light, Catapults and Windmills

Today was not O's best day, but BJ sailed through it. Not sure exactly was on O's mind, but he struggled through the the section on the eyes. Maybe a lack of interest... hmmmm.

The section on mirrors and our experiment with mirrors replicating images kept him occupied and interested for a while though.

I let O take the pics of his brothers catapult experiment.

Here are the instructions and the supplies needed for the task at hand. :)  This week I got everything together for all the experiments. Gave him a list to choose a couple from that I thought would best demonstrate the lessons were were covering, then I let him choose a couple he would like to do.

Since all the supplies were at hand he was able to read from the list what was needed for this experiment, pull them out and begin with little help from me. It is rewarding to start handing the reins over, with guidance,  and watch him apply what I have taught him over the years.

This is the top section of the catapult. The instructions were not very specific and BJ just winged his way through the cutting phase. He did well though. Maybe a little to deep of a cut in the valleys. Leaving the sides high like that later caused them to fold in inbetween each shot.

It was fun watching the marshmellows fly.


The instructions were not as good as I would have liked in the Gizmo and Gadgets book.

There should have been more stabilization to the marshmellow holder.

Also, many of the experiments show a drawing of the finished product given with basic instructions. You have to wing it to complete it. This can be a challenge at times and for some people it might be next to impossible and they will say that's cool and move on the the next experiment without even trying.

This was one of those experiments.

For the part that held the marshmallow the instructions said use a small box such as a small match box. Right! how many people have those little boxes around? The alternative was to make one out of an index card. And that was the extent of the suggestion. No measurements, no pattern. Fortunately I do okay with spatial concepts and I was able to figure out how to cut the card and fold it, but this would not have been an easy task for some. Especially a young person with few life skills to draw on to complete the task.

This was another experiment with kinetic energy. While holding one coin, he shoots a coin against the stable coin. The energy is transferred through the stable coin to the coin on the other side.

The spoon was a hand held catapult. Simple, yet effective, it demonstrated the power of catapults more than his first catapult.

I enjoyed the rattlesnake egg experiment. I remember buying one of these as a kid. Using a bent paper clip, rubber bands and a washer this was a fun example of elastic energy.

O is experimenting with light and reflections off mirrors. He wrote the word Boo backwards on a sheet of paper and then held it up to the mirror.

Since images are reversed in a mirror he was able to read it quite well.

I wrote this sentence backwards for him to decipher.

Here we are seeing a simple example of concave and convex reflections.

 Notice the concave reflection is upside down. If it were a larger reflective surface it would also be more evident that the reflection was thinner as well. 

In the convex image all is right side up but the reflections are usually shorter and more squat.

Both of these are simple exercises demonstrating the light rays being bent on non flat reflective surfaces.

This experiment kept him entertained for a while. The farther away the two mirrors are from each other the fewer images. The closer together their are the more the replication increases. He was able to get them close enough to count 16 images. This is an example of light rays bouncing from one mirror to the next.