Color Mixing with Spinning Tops

What color do you get when you mix red and green?

Well, the correct answer is: It depends!
But before we continue with the theory, lets start with our project:

Here is the printout template for the discs.
It includes the 3 color disks shown above plus a another one (can you guess what colors it will show when rotated?). Additionally there are 2 discs you can color yourself.

To print out the file you need a PDF reader like the one from Adobe.

Then cut out the discs, make a hole in the middle and put it on to your spinning top.
Fix the disc with a bit of sticky tape.

Don't have a spinning top? You can easily build one yourself. Cut out a disc from stiff cardboard and stick a toothpick through its center. That's it. 

So what do you get when you mix red and green?

With water colors that would be some dark brownish color. But with our spinning wheel you would get yellow! In physics this is called Additive Color. 

As you can see, mixing red, green and blue gives you a white! We can prove this with our spinning top. Look at the outer ring of the first disc shown above. Well, I admit it's more like a gray, but the color is gone. To get a white (or at least a brighter gray), look at the middle ring of the same disc. Here the colors yellow (red + green), a light blue (green + blue) and some pinkish color (blue + red) are mixed.
You can experiment with your own combinations  using the uncolored discs on the printout. 

Have fun!