Close your eyes and imagine that you are at a circus. Can you smell the popcorn? Can you hear the elephants? Open your eyes and what do you see? Flashing lights and bright colors! Clowns and circus performers. There are some truly amazing sights at a circus!
Under the circus tent there are lots of lights that help point your eyes towards the ring where the performers are. See how different colors of light mix together in this project.
Did you know that all white light (the kind from a desk lamp, ceiling fan, and the sun) is actually made of many colors? For a light show at the circus colored filters break up the white light into colors like red, blue, and green. A filter is a colored piece of plastic or glass that only lets light of that color through. For example, a green filter turns white light into green light. In this project, you made your own filters using cellophane. Using red, blue, and green lights you can combine them in just the right way so that it turns into white light. Light mixes in different ways than crayons or markers do. The more colors of crayons you mix, the darker your picture ends up looking. With light, it's the opposite. The more colors of light you add, the brighter it seems to be.
How do the circus performers fly through the air like that? Well, acrobats have to train for many hours just like athletes. They practice a lot before their big performance. Acrobats like tight rope walkers and trapeze swingers also use a kind of science called physics to help them. Physics is the study of force (pushes and pulls) and motion (how things are moving).
Sometimes on the trapeze one acrobat will catch another mid-air. To be able to catch hands in the middle, they have to time their swings just right. For example, the acrobat with the shorter rope will have to swing out slightly after the acrobat with the longer rope. Even if their ropes are the same length, the acrobats probably weigh different amounts so they will swing at different speeds. In physics terms, the acrobats use different amounts of force to meet up in the same place. Try swinging with a friend at a playground to see something similar. Because you are swinging at different speeds (and the swings might even be different lengths) you will almost never be in the same spot as your friend.
Tight rope walkers balance very carefully on a thick wire that is high up in the air. To do this, they sometimes carry a long pole that makes it easier for them to balance! Do you remember when you first learned to ride a bike? Maybe you're even still learning! To learn to ride a bike you start off with training wheels. Once you get used to how a bike works, the training wheels come off and you can balance on just two wheels. This is the same for tight rope walkers. At first they learn balance by using a pole, and then they can walk without the pole. Have you ever almost tripped and caught yourself by putting your arms out to your side? This helped balance your body, didn't it? The pole that tight rope walkers use is very similar. It helps them stay balanced over the rope instead of falling to one side or the other.