Colors in a Rainbow

Have you ever seen a rainbow after a rainstorm? It looks like a giant painted arch in the sky. A rainbow shows us the hidden colors in sunlight. Sunlight looks white to our eyes. But white light hides a big secret. It holds many different colors inside it!

In our last lesson, we learned about light. We learned a fact about white light. White light is a mix of many colors. A rainbow proves this fact. It spreads the white light out. Then we can see every single color clearly. Rainbows are very beautiful. They are also a fun science puzzle. We can learn a lot from them.

The Spinning Color Wheel

How do we know white light holds colors? You can test this idea with a simple toy. Imagine a spinning top painted with rainbow stripes. You spin the top very fast on a table. The colors blur together.

In plain terms: if you paint a toy top with rainbow stripes and spin it fast, your eyes will just see the color white.

Your eyes mix the moving colors into plain white. Sunlight does the exact same thing. It brings all the bright colors together into one beam. A rainbow works like the spinning top in reverse. It splits the white beam apart. Then the hidden colors become visible again. You can see each separate stripe.

Meet the Colors in Order

A rainbow always follows strict rules. We call this full set of colors the visual spectrum 2. The colors always appear in the exact same order. They never mix up. They never change places.

The red stripe always sits at the very top. The violet stripe always sits at the very bottom. Let us look at the full list of colors.

Order	Color	Everyday Example
1	Red	A shiny fire truck.
2	Orange	A round, ripe pumpkin.
3	Yellow	A bright, sour lemon.
4	Green	Fresh summer grass.
5	Blue	A clear daytime sky.
6	Indigo	Dark blue denim jeans.
7	Violet	A soft purple flower.

You can see these seven colors in every rainbow. You just need to look closely at the sky. The order is always perfect.

A Helpful Name to Remember

It can be hard to remember seven different colors. You can use a simple trick. Just remember the silly name ROY G. BIV. Each letter stands for one color in the rainbow.

This trick makes learning the order very easy.

Say the name ROY G. BIV out loud. R stands for Red. O stands for Orange. Y stands for Yellow. G stands for Green. B stands for Blue. I stands for Indigo. V stands for Violet. This memory tool works perfectly every time. You will never forget the rainbow order again! You can teach this trick to your friends.

How Water Drops Make Magic

Why do these colors appear in the sky? You need two things to make a beautiful rainbow. You need bright sunlight shining down. You also need tiny water drops in the air.

The water drops act like tiny glass prisms. Sunlight enters a round water drop. The drop bends the light beam.

In plain terms: the water drops split the white light into all the different colors of the rainbow.

Red bends just a little bit inside the drop. Violet bends a lot more than red. This spreads the colors out into a wide band. Soon, we will learn about light waves. These waves help explain this neat bending trick! We will also learn more about the air around our planet. We will learn about other tiny bits in the air.

Finding Rainbows Around You

You do not have to wait for a rainstorm. You can find rainbows in your own backyard. You just need a garden hose on a sunny day. Turn on the hose to make a fine mist.

Stand with your back to the bright sun. Spray the mist into the air in front of you. Look closely at the tiny water drops. You will see a small rainbow appear! You will see ROY G. BIV right in your yard. It is your very own visual spectrum 2.

Key Terms

• Visual spectrum 2 — The full set of colors that make up white light, seen in a rainbow.
• Component colors 3 — The individual colors that mix together to make white light.
• Rainbow 3 — A band of colors in the sky made by sunlight bending through water drops.