- A bowl filled with water
- Clear nail polish
- Rectangle pieces of black paper
- paper towels
1. Drip one drop of nail polish into the bowl of water.
2. Now dip a piece of black paper into the water and pull it out. That’s it!
Put the pieces of paper onto paper towels to dry after dipping them in water.
Once the paper is dry (this only takes a few minutes) tilt the paper in different directions to see the rainbow patterns appear. Hold it next to a sunny window for best results!
Things to take care:
The nail polish dries quickly on the surface of the water, which creates a film that won’t stick to the paper. To do this activity successfully it needs to be done quickly. Be sure to dip the paper into the water within 10-15 seconds after the drop of nail polish goes in.
If the nail polish does create a dry film on top, simply scoop it off and try again more quickly!
The Science Behind Rainbow Paper
When you dip the paper into the water it gets coated with a thin layer of nail polish. The rainbow colors you see are caused by thin-film interference. (Thin film interference occurs when light waves reflecting off the top and bottom surfaces of a thin film interfere with one another. This type of interference is the reason that thin films, such as oil or soap bubbles, form colorful patterns.)
You will notice that the colors on the paper change as the you tip the paper back and forth. This happens because light hits the paper at different angles as you tip it.
The colors of the rainbow vary with the thickness of the nail polish on the paper. This is why each piece of rainbow paper is varied and unique!
This is the same effect you will see when oil mixes with water on the road on rainy days. Thin film interference is also visible on the surface of soap bubbles at just the right angle to the light.