In the air section you can find how to use science to perform magic tricks based on the light properties and how to enhance any magic show.
These tricks and ideas can be used in any science projects or just for fun.
Click on the list bellow to find how to perform it.
- Can we see in the dark
- A pinhole camera
- How do you really look
- How to make a periscope
- Bending light rays
- Reading glass
- What causes the shadow
- How to make a rainbow at home
- Amazing colors
Can we see in the dark
All you need is: shoe box (other box that can be closed tightly), pencil, ball.
Step 1: Make a pinhole in the side of a box.
Step 2: Put a ball and a pencil in the box.
Step 3: Cover the box and look through the pinhole.
Do you see the ball or the the pencil? Do you see anything?
Step 4: Take off the cover of the box as it shown on the picture. Look through the pinhole again.
Do you see anything now?
What you will see: You cannot see the pencil and ball when the cover is on and you can see both when the cover is off. With the lighted flashlight inside, you can see flashlight, ball and pencil.
Why: Without a source of light (such as the sun or the flashlight) you cannot see. You cannot make out either shape or color. Light comes to our eyes in two ways.
Light from the sun or the flashlight or other luminous objects comes directly to our eyes. This is how we see the stars, lightning, an electric bulb, a match or a candle. But we cannot see a ball or a pencil directly.
Light from the flashlight hits the ball and bounces back (is reflected) to our eyes. We see people, chairs, trees because light is bounced off them.
A pinhole camera
You need: cereal box, tissue paper (or onionskin), tinfoil, black crayon, cellophane, flashlight
Step 1: Cut an opening about 3 inches square out of the bottom of a round cereal box.
Step 2: Paste very thin paper over this hole.
Step 3: Cut another square hole, about the size of a small postage stamp, in the center of the top of the box.
Step 4: Cover this new square hole with tinfoil.
Step 5: In the center of the tinfoil make a small hole with a pin.
Step 6: Cut out a paper doll and crayon it black.
Step 7: Tape the doll with cellophane tape to the glass of a flashlight.
Step 8: Hold the box about 2 feet away from the lighted lamp (preferably in a darkened room). Point the pinhole at the lamp and look at the tissue paper.
What you will see: An image of the doll is thrown on the tissue paper-upside down.
Why: The rays of light travel in straight lines from the lamp to the image, as shown in the illustration. This is what happens in our eye. The image forms upside down on the retina.
How do you really look
You need: 2 pocket mirrors, a tape, a book, a clock.
Step 1: Take the mirrors and tape them together so that they form a right angle.
Step 2: Face the clock toward the two mirrors (just infront of the angle).
Step 3: Open and face the book toward the two mirrors.
Step 4: Try to read what you see in the mirrors.
Step 5: Try to look at yourself in the mirrors wand try to comb your hair.
What you will see: You can read the clock and the book. You look strange and you can't seem to comb the side of the hair you mean to.
Why: Light from the left side of your face hits the left mirror and is reflected to the right-hand mirror, which reflects it back to your eye. The same thing happens on the other side of your face.
Thus you see yourself as others see you, instead of the way you usually look in the mirror.
How to make a periscope
You need: a milk carton (cardboard, wooden box), 2 pocket mirrors.
Step 1: Take the box and cut a hole on one side of the box, near the top, and a similar hole on the opposite side, the same distance from the bottom.
Step 2: Tape two pocket mirrors in place parallel to one another, at a 45-degree slant.
Step 3: Hold the box up to your eye and look through the lower hole.
Step 4: Go to a comer and hold the box so that one hole is sticking out.
Step 5: Look through the other hole.
What will see: You can see what is above you and on the opposite side of the box. You can also see around comers. Amazing, isn't it?
Why: Light is reflected by the mirror on top of the periscope to the mirror on the bottom. An object facing the top hole can be seen through the bottom hole. Just as a periscope used in submarines.
What you will see: When you look at the pencil from the side, the pencil appears to be bent or broken at the point where it enters the water.
Why: The light rays appear to the bent because the speed at which they travel in the thicker water is slower than in air. Light travels in air at the high speed of 186,000 miles per second. It travels 3/4 of that speed in water. The bending of light is known as refraction.
What you will see: The print appears larger.
Why: Because the glass is curved, the light rays enter it on a slant and change direction as they go through the water. This is how a magnifying lens works.
What causes the shadow
You need: a dark room, flashlight (or a shaded lamp bulb), white wall.
Step 1: In a dark room, shine a strong flashlight on a white wall.
Step 2: Place the lamp 5 to 10 feet from the wall.
Step 3: Stand behind the lamp/flashlight. Do you make a shadow?
Step 4: Hold up your hand, or stand between the lamp/flashlight and the wall. What happens?
Step 5: Move farther away from the light and closer to the wall. What happens to the shadow?
What you will see: You do not cast a shadow when you stand behind the light. You cast a big shadow when you stand near the light and far from the wall. As you move farther from the light, the shadow becomes smaller.
Why: You cast a shadow by blocking the rays of light. As you move away from the source of light, your shadow becomes smaller because you cut off fewer of the light rays. Any object that won't permit light to pass through creates a shadow, an area of lessened light.
How to make a rainbow at home
What you need: a glass of water, a window ledge, bright sunlight, a sheet of white paper, a mirror, a tray.
Step 1: Stand a glass of water on a window ledge in bright sunlight.
Step 2: Place a sheet of white paper on the floor.
Try the other experiment like this:
Step 1: Set a tray of water in bright sunlight.
Step 2: Rest a mirror upright against one edge of the tray.
Step 3: Look at the wall.
You will see: The colors of the rainbow.
Why: When the light passes from the air through the glass or water, the rays change direction. This called refraction (it's a change in direction of a wave due to a change in its speed). You know the white collar of the light consisst differet colors. Each one of them is bent differently. It's good to know that the violet is bent the most and red the least. When the light comes out of the glass or water, the different colors travel in slightly different directions and strike the screen at different places.
The rainbows that you can see from time to time in the sky after raining days are made when sunlight shines through water dropsin the air.
You need: a cardboard disk, water colors (poster paints), a piece of string.
Step 1: Color one side of a cardboard disk red and the other side blue.
Step 2: Punch small holes on opposite sides of the disk.
Step 3: Thread short lengths of string through each hole.
Step 4: Hold the cardboard by its strings and twirl it around.
What you will see? Try it again with other colors - for example blue and yellow.
What will you see: The color you see is purple. It the second case the color will be green.
Why: You see a third color when your eye and your brain mix the colors of the rapidly whirling disks. This happens because the eye continues to see each color for a short time after it has disappeared. It's because the time of changing the colors (the speed of twirling is) is shorter than the time your eye need to transfer the information it's seen to your brain.