Today we are going to teach you how to create your own rainbows – rain or shine, day or night!
To start this experiment all you need is:
- A clear drinking glass, mostly filled with water
- A source of light (this can be the sun, a flashlight, or other light source)
Begin by filling a drinking glass full of water.
Next, you will need to cut a slat in your sheet of paper (you will want to cut a vertical, thin rectangular shape).
Secure your slatted piece of paper to the outside of the glass so that it is centered more closely to the top of the glass.
Turn on your flashlight, and shine it down at an angle so that the light hits the top of the water in the glass and find your rainbow! It depends upon where your light angle hits the water and reflects unto the surface below as to how far away your rainbow will appear.
What’s the science?
You probably noticed that this doesn’t look like your average outdoor rainbow. The flashlight’s ray contains different colors that create light (such as red, orange, yellow, green, blue, and purple). When you shine the light through the water, it bends and separates into the different colors. This is due to the fact that the different colors (or wavelengths) of light behave slightly differently as they travel through our variables of water and glass.
Remember, it is important to note that an experiment uses a variable (something that changes) to answer a question. To turn this demonstration into an experiment, you have to change something! Check out these questions to get you started:
- How does the placement of the paper affect the outcome?
- Do different light angles change the size of the rainbow?
Give it a try and let us know how your experiment turned out on our Facebook, Instagram, or Twitter pages using the hashtag #gscscience!