Easily Peel a Hard-Boiled Egg

You're an adult making adult food decisions, like cobb salads and egg salads and devilled eggs for your family pitch-ins. (Uh, yeah you gotta pitch-in now.) You don't have time to sit and pick off little shell crumblies like some dumb, desperate kid after an Easter Egg hunt. Here's a quick way to peel an egg, you kidult.

Freeze Water Instantly

When purified water is cooled to just below freezing point, a quick nudge or an ice cube placed in it is all it takes for the water to instantly freeze. You can finally have the power of Fr ozone from The Incredible on a very small scale! Check out the video on this "cool" experiment. 

Make Objects Seemingly Disappear

 
Refraction is when light changes direction and speed as it passes from one object to another. Only visible objects reflect light. When two materials with similar reflective properties come into contact, light will pass through both materials at the same speed, rendering the other material invisible. Check out this video from Brit Lab on how to turn glass invisible using vegetable oil and Pyrex glass.

Make Slime with Glue and Borax

You will need

• Elmer’s glue (most kinds of white craft glue will work)
• 2 disposable cups
• Food coloring (you pick the color)
• Water
• Borax Powder (available at most large grocery stores near the laundry detergent)
• A plastic spoon (for stirring)
• A tablespoon (for measuring)

What to do

1. Fill one small cup with water and add a spoonful of the Borax powder and stir it up. Then set it aside.
2. Fill the other small cup with about 1 inch (2.5 cm) of the glue.
3. Add three tablespoons (20 ml) of water to the glue and stir.
4. Add a few drops of the food coloring and stir it up until mixed.
5. Now the fun part…Add one tablespoons of the Borax solution you made earlier and stir well. Watch the slime form!
6. After the slime forms let it sit for about 30 seconds and then pull it off the spoon and play with it!

Tip: Keep your slime in a tightly closed plastic bag when you are not playing with it, and keep it away from carpet and your little sister’s hair.

How does it work?

Now for the SCIENCE part…. This POLYMER is unique because it has qualities of both a solid and a liquid. It can take the shape of its containers like a liquid does, yet you can hold it in your hand and pick it up like a solid. As you might know, solid molecules are tight together, liquid molecules spread out and break apart (drops) POLYMER molecules CHAIN themselves together (they can stretch and bend like chains) and that makes them special. Jell-O, rubber bands, plastic soda bottles, sneaker soles, even gum are all forms of polymers. The polymer you made should be kept in a sealed plastic bag when you aren’t playing with it. Also, be sure to keep it away from young kids or pets who might think it’s food. Have fun!

MAKE IT AN EXPERIMENT

The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions:

1. How can you make the polymer stretch the farthest?
2. Does the amount of Borax added change the slime?
3. What method of storage will make the polymer last the longest?
4. What brand of glue makes the stretchiest polymer?
5. Does the amount of water added to the glue affect the gooeyness of the slime?

Science Bob

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Build A Hovercraft You Can Ride!

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 Hovercrafts are lots of fun, and a great way to demonstrate the power of moving air. Here are the instructions to build a hovercraft of your own that you can ride on. Construction time can be as little as a few hours. These plans are based on the plans we used for the hovercraft built for Jimmy Kimmel Live. (see video) To build a smaller, tabletop hover craft powered by a balloon, click HERE.

You will need:

• 4’ X 4’ 3/4 inch plywood
• Piece of heavy-duty tarp material 5’ X 5’
• .25 inch machine bolt (1.5 inches long) with nut
• 2 2-inch washers for the bolt
• Plastic cover for a round electrical box
• Leaf blower (cordless electric leaf blowers are great – we used a Makita BUB182Z)
• Lawn chair (optional)
• String
• Pencil
• TOOLS: (adult use only) jig saw, staple gun, drill, utility knife, sandpaper

Keeping Water Separate

Fill two identical glasses with water. Add two tablespoons of salt to the water in one glass and stir well. Add a few drops of food coloring to the water in the other glass.

Cover the glass containing the colored water with a sheet of paper, turn it upside down and place it on top of the glass containing salt water. (Be sure to do this trick over a saucer or bowl.)

Gently pull the paper out from between the glasses. The colored water and the salt water will remain separate.

How Does It Work?

Salt water is heavier than colored water, so the two stay separate as long as the boundary between them isn’t disturbed. Try turning the two glasses over, though. The heavier salt water will now be on top, so it will flow down and mix with the colored water.

Toothpick Torpedo

Dab a little shampoo on the blunt end of a wooden toothpick.

Drop the toothpick in a pan of water. The toothpick will start moving in the direction of the sharp end.

How Does It Work?

Shampoo contains agents that reduce the surface tension of liquids. As the shampoo on the end of the toothpick dissolves, it reduces the water’s surface tension around it, thus releasing the water’s hold on that end of the toothpick. The water around the other end of the toothpick still has surface tension, so it pulls the toothpick in that direction.

Egg Into Bottle

Find a glass bottle that has a mouth slightly smaller in diameter than an egg. Pour some hot water into the bottle (be careful!), shake it vigorously and empty the water.

Peel a soft-boiled egg and place it on the mouth of the bottle. Leave it there for a while and it will get sucked inside.

How Does It Work?

The vapor from the hot water drives the air out of the bottle. Once the egg seals the top of the bottle, the air can’t get back in. As the water vapor cools, it turns back into water, causing the pressure inside the bottle to drop. The higher pressure of the outside air pushes the egg into the bottle.

Reading Through an Envelope

With a black felt-tip pen, write a three-letter word in large letters on a white piece of paper. Place the paper in a brown envelope, and insert that envelope into a white envelope. The writing on the paper should now be impossible to read.

Get a piece of dark construction paper or tear out a page from a magazine that is printed on both sides. Roll up the paper into a four-inch-long tube. When you hold the tube against the envelope, you’ll be able to read the writing inside.

How Does It Work?

Usually you can’t read the writing inside an envelope because of the light reflected off the envelope’s white surface. But the tube blocks that reflected light, so you see only the light coming through the envelope.

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A Can That Can “Walk”

Place an empty aluminum can on its side on the floor. Blow up a balloon and tie a knot in the end. Rub a tissue back and forth on the balloon.

When you put the balloon near the can, the can will start rolling toward the balloon.

How Does It Work?

When you rub the balloon with a tissue, the balloon gets a negative electric charge of several thousand volts. When you put the balloon near the can, electrostatic induction affects the molecules in the metal. The outside of the can gets a positive charge, so it is drawn toward the balloon and starts rolling in that direction.

Bending Light Through Water

Punch a hole in a clear plastic bottle two inches from the bottom. Put your finger over the hole, fill the bottle with water and cap it to keep it from draining out.

Darken the room and cover part of a flashlight with your fingers to make the beam narrower. When you take the cap off the bottle, the water will flow out in an arc. Shine the flashlight at the stream from the side of the bottle opposite the hole. The light will bend with the arc and create a bright glow where the water hits the sink.

How Does It Work?

When the light in the stream strikes the boundary between the water and air, much of the light is reflected back into the stream. The light continues this internal reflection all along the arc formed by the falling water. The same principle is used to transmit light signals through flexible optical fibers.

A Flying Trash Bag

Hold the mouth of a black trash bag in one hand. Use a hair dryer to blow hot air into the bag.

Seal the mouth of the bag with tape. Tie a long piece of string around the tape so you can hold it. Take the bag out into the sun. The bag will rise slowly into the air. (It’s best to do this trick in an open area on a windless day.)

How Does It Work?

Since the bag is black, it absorbs heat from the sun. That heat makes the air inside the bag expand and become lighter. When the bag and the air inside are lighter than the surrounding air, the bag starts to rise.

A Candle That Sucks Water

Place a candle upright in the middle of a saucer. Fill the saucer with water. Light the candle. Place a glass over the candle. When the flame goes out, the water in the saucer will get sucked into the glass.

How Does It Work?

When the candle is burning inside the glass, the heat makes the air expand, so some of the air escapes outside the glass. The candle goes out after it uses up all the oxygen, so the air inside the glass cools. As it cools, the pressure inside the glass drops. Some of the carbon dioxide formed by the flame dissolves in the water as well, decreasing the pressure even more. The water outside the glass on the saucer is forced into the glass by the higher aire pressure outside.

Pepper Magic Trick

SCIENCE TRICK WITH PEPPER

Science experiments that look like magic are always big hits! And with this pepper experiment, all the ingredients are things that everyone has in their kitchen, so you can do it TODAY!

SCIENCE EXPERIMENT SET UP

• pie tin
• water
• ground pepper
• liquid dish soap OR a bar of soap

Add the water to the pie tin. Then sprinkle the pepper on the water — really cover it, as the more pepper there is, the more dramatic the experiment will be.
Then ask your child what will happen when she dips her hands in the pie tin. Then let her (nothing will happen). Then ask what if she puts a dab of liquid dish soap on her fingertips and puts it in. Then let her try! The pepper will scatter away from her finger!
You could also try this with a bar of soap rather than the soap on the finger – it’ll do the same thing!

This pepper science experiment looks like magic! But, of course, it’s really science! Water has a high surface tension. The pepper floats on top of the water, but when you add the soap, the surface tension breaks…and the pepper scatters!

I’ve heard that using sugar will send the pepper back. I haven’t had much luck with that though. When we sprinkle sugar the pepper goes back a little – but only if you are really looking for it. Am I doing something wrong? Let me know! Leave me a comment or email me!