Electricity and Magnetism Unit Study (II)

I decided it was time for another Electricity Unit mostly because Teddy had been asking me tons of questions about electricity, and has also been very fascinated with/scared of (those two things often go together) lightning lately. It was funny to realize that the girls haven't learned any of this either, since we last did this unit in 2014. Malachi claims to remember everything, but he was only 6, so I'm not sure I believe him. But he was like Teddy back then—very curious and inquisitive and serious about learning, and a FULL participant in everything we did, so maybe he does remember!

I also feel like I did a more complete job on this unit the previous time through. Abe and Seb both understood a lot about electricity already, and helped me figure out a lot of things! And they were very excited and eager to do all the activities, which is always helpful. I was surprised how much the girls liked working with the snap circuits, etc., too this time—but they weren't AS fanatical about it as the boys were back then. I think this subject was just of particular interest of both of those older boys!

Here is the pinterest board from 2014, with perhaps a few pins added this time: https://www.pinterest.com/marilynnielson/electricity-and-magnetism-homeschool-unit/

A good place to start when talking about electricity is with the structure of the atom, and by explaining how ions work. Here are the children playing the "pass the electron" game (we do something similar to this one: https://www.nationalgeographic.org/activity/circuits-friends/print/)

Here are some explanatory videos we watched:

Ions: https://www.youtube.com/watch?v=bnudaqeTyto
Atoms: https://www.generationgenius.com/videolessons/atoms-and-molecules-video-for-kids/

More activities we did last time: https://nielsonschool.blogspot.com/2014/04/electric-current-conductors-and.html

Luckily, we still had most of our electricity and magnetism supplies from last time. They're great to have around for homeschool in general. Here's the list of supplies I made last time, and links to where to get things. Annoyingly, some links are broken, but a google search for that item usually yields lots of choices.

Here are some other videos we used:

Intro to circuits (beware annoying narrators): https://www.generationgenius.com/videolessons/electricity-and-circuits-video-for-kids/?gclid=CjwKCAjwhMmEBhBwEiwAXwFoEW1-Ub4d055l4boFmt-kvSXoab4mptqupBftaK02wHecFK9qWMYfRhoC76IQAvD_BwE 

Make sparks http://www.learnplayimagine.com/2013/04/how-to-make-lightning.html

Slow motion lightning strikes: https://www.youtube.com/watch?v=KO3H285CFRo

The electric eel https://www.youtube.com/watch?v=z0M7_HPSi14

Make a telegraph machine https://www.energizer.com/science-center/how-to-make-a-simple-telegraph-set

Virtual coal power plant tour https://www.youtube.com/watch?v=2IKECt4Y3RI
Nuclear power plant tour: https://www.youtube.com/watch?v=_AdA5d_8Hm0
Hydroelectric: https://www.youtube.com/watch?v=Ki8kSB1ThJQ
Substation: https://www.youtube.com/watch?v=7Q-aVBv7PWM

You can learn a lot just by playing around with making your own circuits. The children had a lot of fun doing that in an open-ended way with all the supplies we had. Snap circuits are, of course, fun too, but they don't have the immediacy of a real circuit with a bulb and battery you add in yourself. 

More ideas for circuit exploration: https://nielsonschool.blogspot.com/2014/04/simple-foil-circuits-series-and.html

And some further study of switches and resistors: https://nielsonschool.blogspot.com/2014/04/resistors-and-switches.html. That link includes an explanation of three-way switches, which I had forgotten and had to relearn this time. Here's Daisy giving another explanation of it:

And a few more resources:

• Make a three-way switch https://www.youtube.com/watch?v=6_TpKdYeQaU

• Make paper circuits with pencil https://www.youtube.com/watch?v=BwKQ9Idq9FM
• Make foil circuits https://www.youtube.com/watch?app=desktop&v=qJDgl9eVpy8

Making a homemade light bulb is always fun! It's so dramatic when it burns out.

Instructions here: https://nielsonschool.blogspot.com/2014/04/homemade-light-bulb.html

Or you can refer to these pictoral instructions: https://www.wikihow.com/Make-a-Light-Bulb

We talked about batteries and made a voltaic pile. (You can also dissect a battery—see that same post)

See also:

• Voltaic pile https://www.sciencebuddies.org/science-fair-projects/project-ideas/Energy_p015/energy-power/make-a-battery-from-coins#procedure

• Hand battery https://www.exploratorium.edu/snacks/hand-battery

Success! The voltaic pile powered our LED.

I remembered that we all enjoyed making these slider cards last time, so we did that again. (Video tutorial here: https://www.youtube.com/watch?app=desktop&v=aurnw8C1aUc) The subject of the slider card was supposed to be something to do with electricity. Let us see if the children followed these instructions. Junie made a cool lightning storm.

Daisy showed a circuit working and explained how it worked.

Goldie drew…the Teddy Bears' Picnic?

And Teddy drew…a tree in summer and winter (plus a green bunny and an "I love you" for me. Sweet.)

Cleaning pennies is a cool demonstration. We also did a simple form of electroplating that was a little different than what we did last time. We had a buy a copper pipe at the hardware store to get our copper ions off of. A few weeks later, that pipe turned out to be the exact right size to replace a towel bar that had broken in one of our bathrooms. How lucky! :)

Some of our electroplated coins

Resources: 

• Clean pennies with vinegar https://sciencebob.com/clean-pennies-with-vinegar/
• or this https://www.thoughtco.com/chemistry-fun-with-pennies-602055

• Copper plating a nail https://www.youtube.com/watch?v=T3qhqTVssoo
• Or here: https://www.youtube.com/watch?v=gTjWkeSpRqk

• How Electromagnets work https://www.youtube.com/watch?v=cxELqN7wjS0

• How a doorbell works https://www.youtube.com/watch?v=1R5ED5qHWZc

We also tried our hand at making paper circuits with copper tape. 

(see instructions: https://www.sciencebuddies.org/stem-activities/paper-circuit#summary)

It was surprisingly tricky to make the circuit complete AND make it fit with the drawing you wanted to do! Daisy made a glowing penguin.

Teddy made a green-eyed bunny.

Malachi made…this

Junie made this terrifying monster

And Goldie made a really cool lightning storm!

Here are a few more links for studying magnetism:

• Making 3-D Magnetic Fields

• More magnet play

Firefly Glowstick Games

When we studied fireflies, we learned that each species uses a distinctive flash pattern to identify themselves and attract mates. So, to demonstrate this, we went over to our church gym (because it was a nice big space to run in, and because we couldn't find a place where it would be pitch dark in our house) and I brought glowsticks in three color pairs: two pinks, two blues, two greens. I gave one glowstick to each child. Then we turned out the lights, and the children that had matching colors had to find each other by flashing and waving their lights.

It was surprisingly fun. They had fun locating their "mates," but then they came up with all kinds of other firefly games too--races and relays and so forth. The glowsticks gave off just enough light that you could (mostly) avoid running into walls, but it was dark enough that everyone was laughing and squealing and having near-collisions. Good times.

Glowsticks are a pretty good representation of a firefly's bioluminescence, since they are both "cold" light created by chemical reactions. We so wish we had fireflies around here, because we love them! But at least some of us have finally have seen them in real life, when we went to Montreal last summer. And maybe someday we'll really get lucky and see some here in Utah!

Firefly mates finding each other

Fireflies starting a race

Holograms

This is a great site, but overwhelming because there is just so much information to get through! His diagrams are really clear, though, and it would be really cool to make your own holograms as he describes.

Probably the best of these videos on how holograms are made.

Good explanation of holograms, and why "3-D" movies don't actually give you the same type of experience—but maybe they could someday!

Maybe like this: here is a demonstration of some new technology that can project text and images in mid-air. It works by ionizing the molecules in the air to make them light up.

Another video of the same technology.

This isn't actually using holograms, but digital projection that makes things look they are present in 3-D through optical illusion and angled screens. I think these images are often called holographic.

Making a Laser Projection Microscope

We learned about this awesome project from The Happy Scientist (subscription required for this video). He gave a great, simple explanation about what to do, and we had no trouble getting it to work. And it was so cool! You can probably find other tutorials for this project online, also. (Yes. Here is one.)

Basically, what you're doing is creating a little loop in which a drop of water can be suspended by surface tension. The water acts like a lens for the laser light to shine through. The light is then projected onto a screen and, voila!, you can see tiny little microorganisms in the water. It is amazing. We used pond water to make sure there would be lots of life in it, and there was! We saw all types of different protazoa, flagellates, etc., with all types of movement going on. Some things zipped across the screen quickly, some sort of lurched along, others were definitely swimming. So cool! This is one of the most impressive activities we did this entire unit, and the children LOVED it. They wanted to show it to everyone who came to our house for the next several days.

It's hard to see anything very clearly in the picture above, but this video is really cool. You can see several organisms moving around in the drop of water, and observe the different ways they move. You should definitely try this project yourself!

Lasers

I can't even describe to you how much the children delight in saying "light amplification through stimulated emission of radiation." They think they're so funny. And we loved learning about lasers! They are cool.

This is the laser pointer we have. We really like it.

Here's a good, simple explanation with pictures of how lasers work and what they are.

Lots of good videos about lasers here.

This video was okay—better in conjunction with the others, though, as we didn't think it explained the process very clearly.

This video has no narration, but just text. We liked it because it described semiconductor lasers, which are slightly different than the solid state, gas, dye, or other lasers. (We learned about semiconductors earlier, during our electricity unit, and our favorite video then was this one.)

This one is less about the lasers themselves, but more about laser cutters. Still interesting though.

This was interesting because it showed an open cavity laser, which makes it easy to see what is going on. This is a helium-neon laser.

Very clear and well-explained. Shows why a ruby is often used in a solid-state laser. This video really helped us realize why "pumping" is needed before the laser actually starts working (something we didn't understand before).

Just screens of text. But a good analogy.

Another video that is quite clear about how stimulated emission of radiation is created. Good animations (except the one of Einstein!) :)

Light in Art; Pointillism

It would be a shame to talk about only the science of light and not the importance of light in art, especially with our resident expert to help us out. We actually didn't have as much input from Sam as we would have liked, as the days we studied art and light corresponded with a very busy few days for him, but we had some good books and we really liked the things we did learn.

My favorite book was this one, which talked about how different time periods and artistic movements affected the way artists captured light in their work. It had great examples from a variety of art styles.

We talked a lot about the Impressionist Movement because of those artists' intense focus on capturing light in a scene. Here's a good video we watched about Monet, and we also found several books on him, and other Impressionist artists, at the library.

We also covered Georges Seurat and Pointillism. I found lots of ideas online for art projects related to Pointillism, but for this unit on light we wanted to focus more on subtractive color mixing and the way your eyes mix the separate points of color to create other colors, so we talked mostly about that. Then we made Pointillist pictures with markers (since I felt like adding the actual mixing of paints to this project would just obscure the ideas we were trying to focus on).

I really loved the pictures the children came up with. One of my favorite things was this line of rainbow colors Sebby made, on the bottom right below:

You can see the six boxes with definite colors: pink, orange, yellow, green, blue, purple.

But when you look at them up close, they are just mixed dots of primary colors! So interesting!

Abe's bear

I loved Junie's picture. You can't see all the tiny dots she made, but there are hundreds of them. She worked so hard on this!

I really loved Daisy's ice cream cone (with matching tiny ice cream cone) too.

And we only ruined a few markers! :)

Fiber Optics

We spent a day talking about fiber optics. I knew they used fiber optic cables for transmitting phone and internet signals, but my only real association with fiber optics was a color-changing lamp someone gave our family when I was little, like this:

which I assumed was not really "fiber optic" at all.

But the actual concept, of how light can travel through a flexible glass tube and come out at the end, really is about the same. Here is a demonstration of how light is bent to the "critical angle" so it won't escape the fiber optic cable.

Here's a video on how fiber optic cables are made

Another video on how the cables are made—this one is more technical, but it was still interesting to skim through

We really liked this explanation, and it includes a demonstration you can do yourself with an old plastic bottle.

Another explanation that includes a diagram of the parts of a fiber optic cable.

Some discussion of why fiber optic can be faster than regular copper wire.

Making marbled paper

I've seen this project cited as a good way to demonstrate the different densities of different materials, but we used it when we were talking about color printing in books. This process, where the oil sticks to certain areas of the paper and not to others, is a lot like the way certain colors and dyes are transferred to the page when books and magazines are printed.

I don't know if we did it exactly right—our paper looked very pretty but not nearly like the papers she shows in this tutorial! Still, we had a fun time.

And here's another tutorial here, in case you don't have oil paints to use (we didn't).

Atmospheric lighting effects

We had this book from the library, and we liked it so much that I got it for Sam for Christmas. We love observing/remarking on stuff like this, so it is nice to learn more about HOW and WHY these effects occur!

This video shows the "green flash", which is an interesting phenomenon I'd heard of, but never really understood, before. The book pictured above had a pretty good explanation of why it occurs, to which I doubt I can do justice. But here's a web page about it if you're interested, or this one is a bit simpler. Just like practically everything we learned about in this unit, it seems confusing, then simpler when you first hear it explained, then even more confusing and mysterious the more in-depth the explanation becomes! :)

Here's another video that shows a photographer trying to capture the green flash.

Some other phenomena I've always been interested in are the aurora. I (like everyone else in the world, I suppose) have always dreamed of seeing them for myself someday!
There are some great pictures of the aurora borealis here
And more beautiful pictures here
And this video gives you an idea of how beautiful it must be to see the aurora in real-time!

Prisms, Rainbows, Light Scattering

We liked creating a prism with a mirror, light, and water (something similar is described here) and projecting the spectrum on the wall. So pretty!

Apparatus: water in pan, angled mirror, flashlight

We mixed three colored lights to make white light (additive)

Color mixing (subtractive)

"Daylight"

"Sunset light"

We learned about Tyndall Scattering in the atmosphere—that's the effect that makes the sky appear blue when the light is coming from overhead, and reddish when the light is coming at a sideways angle. A similar demonstration is described here.

Another brilliant spectrum on the wall, from a glass prism this time. It's so fun to play with prisms—I remember doing it for hours at a time when I was little.