Saturday STEM Challenge: Rainbow Scavenger Hunt
This week’s Distance Learning offerings are focusing on optics, light, and the electromagnetic spectrum.
You’ve probably seen a rainbow outside before, but have you ever thought about why you see those colors in the sky? The reason is similar to why you could see the coin in the bowl of water in Wednesday’s At-Home Stem Activity: refraction.
Light travels at a constant speed in a vacuum, but once you send that wave of light through a different material, it slows down. When a rainbow is made, what you’re seeing is white sunlight shining through raindrops. The light enters the water, refracts (bends because it’s slowing down), and reflects off the back of the raindrop back out into the sky.
But like we learned in Monday’s activity, each color of visible light has a different wave length. That means that each color is refracted by the raindrop at a slightly different angle. This causes the white light to split into different colors, which allows us to see a rainbow.
But raindrops aren’t the only thing that splits white light into individual colors. Like we saw on Tuesday with our DIY spectroscopes, a CD breaks up light into a rainbow. So if a CD refracts light, there are probably other things that do as well. And this brings us to this week’s STEM challenge: how many household objects can you find that make rainbows out of white light?
We’ll give you one for your scavenger hunt: A glass of water
When held up in the light…
…the glass of water will act just like a raindrop in the sky, scattering the light and forming a rainbow.
