Have you heard of radio waves, microwaves, and x-rays? These are some of the waves that are on the electromagnetic spectrum. But we can’t see these waves with our eyes. The only waves we can see are on the visible spectrum. Here is a picture of the spectrum, with a flashlight being used with a prism to make...a rainbow?!
What's a Prism? Where do Rainbows Come From?
Let's learn more about this visible spectrum. Here are a couple educational videos that will help us figure out how prisms are used to make visible light, and we'll also figure out where rainbows come from! At the bottom of this blog is a link to another video about making a real rainbow with just a clear glass of water, flashlight, tape, and white paper!
Can you get two baskets or two rugs - or just two spots on the floor - and then go on a prism hunt around your house? Put all the prisms in one spot, and all the non-prisms in another spot. Remember, a prism has flat surfaces, and two sides (like a top and bottom) that are the same.
How many things can you find? Can you find any prisms that have interesting shapes such as triangles and pentagons? Here’s just a handful of things I found, I bet you can find lots more than I could!
Making a Circular Rainbow
One thing I’ve never seen in real life is a full, circular, rainbow! You’d have to be in a very special place to see one, such as Victoria Falls, where you’re high up above the rainbow, and where there’s lots of water droplets and sunlight. We can make our own circular rainbow with paper and circular objects in our house. Let’s hunt for 6 different sizes of circles that we can trace and then cut out! Make sure you put your objects in order from biggest to smallest, with red having the biggest, then orange, yellow, green, blue, and purple having the smallest.
Making the Visible Spectrum
Can you make the visible spectrum with construction paper? I cut out a piece of white paper to be the white light, then I cut a plastic sandwich bag because it looks like a prism! Then I cut out a piece of paper for each color of the rainbow. If you are practicing your writing, it would be great to write and label the following words: white light, prism, red, orange, yellow, green, blue, purple, the visible spectrum.
Making a Rainbow
Do you remember how a rainbow is made? Right, the rain drops are like prisms, and break the sun’s white light into visible light, making a rainbow! First, I colored a rainbow on white paper, and a sun too, then I cut them both out and put them on blue paper. I then cut out some raindrops, drew arrows, and made labels. Can you make a picture like this one?
Making a REAL Rainbow
We've looked at different games and crafts about prisms, the light spectrum, and rainbows, but now let's make a real rainbow! What we'll need is a clear glass of water, a flashlight, a white piece of paper, and some tape. Now you can watch the video below to learn a little more and make your own small rainbow in your house!