Spring is here, which means rainbows! They’re so cheerful and happy and are such a fun, simple way to work on colors. Don’t you just love when science and art come together?
What makes a rainbow?
A rainbow appears when the light gets split up into its 6 different colors: red, orange, yellow, green, blue, and violet.
Usually – the reason the light gets split up is because it is passing through a substance that bends the light. The different colored wavelengths bend in different amounts. Red tends to bend the least, so it appears on the top of the rainbow, while violet bends the most and ends up on the bottom – with all the other colors in between.
When we see a rainbow in the sky, it is usually when the sun is behind us and it is shining through millions of tiny raindrops floating in the sky – all of which are bending the light and projecting the rainbow.
We don’t need raindrops to make a rainbow. There are many different ways to make rainbows of your own…
Making rainbows with a CD
You can make this really simple and just hold a CD up to some sunlight – or shine a flashlight on one in a darkened room – and you will see a rainbow on the CD.
Or go a little further, and try to catch the reflection of the light on some paper!
The reason why a rainbow appears is because there are tiny ridges in the surface of the CD that are reflecting the light in different directions.
Misting a hose on a sunny day
Rainbows are only seen when the sun is directly behind you, low in the sky, and there is a rainfall or mist in front of you. This means the center of the rainbow is always located along a line down your shadow.
Try watering your garden with your back to the sun. Use a misting nozzle or cover the end of the hose with your fingers. Squirt the water in the direction of your shadow and there will always be a rainbow for you to see. Wave the hose around to see the full rainbow. If the sun is high in the sky, you will see a slanted rainbow that you will be standing in.
It sure makes watering a lot more fun!
When it's warm enough, you can run through the rainbow. If you get in close enough, not only will you get really wet, but you will get to see a full circle rainbow floating right in front of your face. Yep, I said, "a full circle!" Give it a try!
Painting the rainbows
Hang a piece of poster board on the wall and lay out some paper on the floor to protect it from drips. Tape pieces of paper to the poster board to use as your canvas and prop up a flashlight to reflect the rainbow onto the paper.
Make a rainbow with a CD as mentioned above. What color do you see first when you look at the rainbow? Move the CD around to create different rainbows and then paint those too.
Red + yellow =?
Yellow + blue =?
Red + blue =?
Rainbow string painting
Paper. I recommend card stock.
Paint. For every color of the rainbow
A large surface to add your paint.
A heavy book (optional)
Start by adding a bead of each color, onto your large surface, so they are touching and forming a line.
Lay your string across the paint and slightly twist so the paint covers all sides of the string.
Lay the string across a piece of paper so the ends hang off the edges.
Place a second piece of paper (the same size if possible) on top.
Press down onto the paper as you pull the string back out.
Note: you can use a heavy book to help hold the paper down.
Remove the top paper to reveal the design.
Repeat until you are happy with the project.
Play I SPY or go on a rainbow scavenger hunt
Dyed pasta rainbow mobile
Put the pasta in a plastic baggie and add about a tablespoon of alcohol. Shake the bag until all of the pasta is coated.
Add in a few drops of food coloring and shake again until the pasta is dyed. Lay the dyed pasta out on a piece of waxed paper to dry.
Once the pasta is fully dry, string it onto yarn and tie the pasta strings onto a clothes hanger.