From the brains behind brains on, this is the moment of um.

Answering those questions that make you go, um, um, um, um, moment of um comes to you from APM Studios. I'm Anna G.

Art was always one of my favorite subjects in school.

When I was in second grade, we had an art teacher, Mrs. Ames, that taught us about primary colors with a little

song that I still remember and went like this. Red yellow blue, red yellow blue, I see you,

red yellow blue, you are the primary colors, you make all the other colors, I wish I were a color just like red, yellow, blue. Yep,

that song is still bopping around my brain 30 years down the road. But looking back on the lyrics,

I have some questions. First of all, do I wish I were a color? Which one? Green, maybe. Yeah,

yeah, a nice mossy green. Okay, that answers that one.

But you know what else I learned in school? I learned that sunlight is made up of all the colors of

the rainbow. If you let sunlight shine through a special glass shape called a prism, it splits the

light into those different colors and you see a little rainbow.

So if sunlight is made of all the colors, who decided that red, yellow, and blue were the

primary ones? Do red, yellow, and blue actually make all the other colors? My friends Evelyn

and Luke might not have had art class with Mrs. Ames, but they've got questions too.

Hi, I'm Evelyn. Hi, I'm Luke and we're from Chicago, Illinois. And our question is, why are primary colors different from the colors of light?

If we want to get the largest range of colours by mixing three coloured lights,

the best we can do is use red, green and blue.

My name is Stephen Westland.

I'm a professor at the University of Leeds.

I literally study every aspect of colour. A set of primary colours is simply a set

of coloured lights or colourance, dyes or pigments. When we mix them together, we can make a wide range

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