Episode 2 - Recreating Really Radical Rainbows
Welcome to Episode 2 of Astrophysics for 8 Year Olds!
In this episode Sophie makes rainbows 3 different ways and talks about how they form.
Free B Roll provided by Videezy.com
Here are the key points:
1. Light is made of waves
The distance between peaks of the wave is called a Wavelength
2. Different wavelengths are different colours
What we see as colours is just light of different wavelengths hitting our eyes.
In this example, the white light hits the tree - most of the light is absorbed, and the green light bounces off.
Use this tool to see the change in colour as you change the wavelength.
In reality, light waves are so tiny, they wobble 100-200 times across the width of a human hair!
wavelength: nanometres
Credit: Combined code for an Oscillating Sine Wave from gkhays and nm to RGB converter from hypercompetent, both on github.
3. When light hits water or any other see through material, it bends!
The pencil and skewer aren’t bent here - it’s the light bending that makes them look like that.
4. Different wavelengths bend different amounts
We saw this with the prism and the glass. The light split into the different colours because the different waves bent different amounts.
In a real rainbow, the light comes from the sun and hits the raindrops in front of you.
The light bends and bounces in the raindrop, splitting off into different colours.
The violet light hits your eyes from raindrops lower down, and the red light hits your eyes from raindrops higher up. This is why red is at the top the rainbow, with violet down the bottom.
