Guilford County Schools ACES Program
Weekly Theme: The Science of Magic – More Activities
Bending Light Experiment - Bending Pencil
Materials you will need:
• Pencil
• Water
• Clear Glass or Jar
Steps:
1. Fill the glass or jar half way with water.
2. Place the pencil in the water.
3. Look at the pencil from the top.
4. Look at the pencil from the bottom
5. Look at the pencil from the sides. Straight or bent? What happens when you look at the pencil through the side of the glass? Light play tricks on your eyes. The pencil looks bent. This is because light travels slower through water than through air. As the light enters the glass of water it slows down (changes direction) and as it leaves the glass it speeds up again – therefore making the pencil look bent!
Jumping Coin
Materials you will need:
Bowl
Cold Water
Glass Bottle
Coin
Steps:
1. Fill a bowl with some cold water.
2. Place the bottle neck and coin in the bowl of water to chill them. This helps to make an airtight seal when you place the coin on the top of the bottle.
3. Place the coin on the top of the bottle.
4. Wrap your hands around the bottle and wait for several seconds.
What happens to the coin?
5. Remove your hands from the bottle and wait.
What happens to the coin now?
Why does the coin jump? When you hold the bottle with your hands, the air inside the bottle heats up. The warm air pushes harder than the cool air that is outside the bottle so it forces the coin up. When the air inside the bottle cools down the coin will stop jumping.
The Sticky Card
This is a really old trick but it always fools your audience. Get a playing card and tell your friends to stick it to the wall. It must stay on the wall when you let go. They will not be able to do it. Then take the card and stick the card to the wall. It will stick for you. The trick is when you walk to the wall drag your feet and build up static electricity. For this trick leather soled shoes work the best. It does not work well in hot or wet weather.
Bending Light Experiment - Rising Coin
Materials you will need:
• Coin
• Water
• China or Plastic (non transparent) bowl
Steps:
1. Put the coin in the bowl.
2. Walk backwards until you cannot see the coin in the bowl any more.
3. Have someone pour water slowly into the bowl.
4. Watch the bowl from where you are standing.
What do you see? When the bowl is empty, the edge of the bowl stops you seeing the coin. When the bowl is full, the light bends over the edge, so you can see the coin. Have you ever noticed that things at the bottom of a pool or river always look closer to the surface than they really are? This is because of the way light is bent through water and is an effect of refracted light.
Floating & Sinking Experiment - Can You Sink an Orange?
Materials you will need:
• A Bowl
• Water
• An Orange
• A Friend
Steps:
1. Fill the bowl with water. What happens to the orange?
2. See if your friend can get the orange to sink.
3. Take the orange and peel it.
4. Place the peeled orange back in the bowl of water. What happens this time?
The orange sinks because the orange peel if full of trapped air pockets, therefore making the orange light for its size (so it floats). When you remove the peel (including the air pockets) the orange weighs a lot for its size. Then it sinks because the orange is denser than the water.
Chemical Reaction Experiment - Green Penny
Materials you will need:
• Saucer
• Vinegar
• A Penny
• Kitchen/Paper Towel
Steps:
1. Fold the kitchen/paper towel a few times to get a bit of thickness.
2. Lay the kitchen/paper towel on top of the saucer and pour out some vinegar until it is soaked up by the kitchen/paper towel.
3. Place the penny on the kitchen/paper towel and leave it there.
4. Keep a check on the penny and observe the chemical reaction.
5. Leave it for a full day to get the best results.
What happened to the penny? It turned green.
The copper in the penny reacts with the oxygen in the air to form the green colored copper oxide.
Air Pressure Magic
Amazing! A full glass of water held upside down without losing a drop of water! Fill a glass to the top with water. Place a piece of paper on top of the glass. Flip the glass upside down really fast and let go of the paper. The water is pushing the paper down but the air around the paper is pushing it up with a stronger force. You can help it by pushing the paper firmly on top of the glass so that no water leaks out. Construction paper works best.
Rise Above Experiment - Mix and Move?
Materials you will need:
• Table Salt
• Two Clear Plastic Cup
• A Spoon
• Tap Water
• Food Coloring
Steps:
1. Add some warm tap water in one of your clear plastic cups.
2. Add a few tablespoons of salt to the water and stir it really well, until the salt has dissolved in the water.
3. Add some warm tap water in your second cup and add a few drops of food coloring and stir to mix the color.
4. Slowly pour some of the food coloring tap water into your salted tap water cup.
5. Give it a minute to do its thing.
What happened? Did it separate?
The colored tap water has move to the top of the salted tap water because salt water is heavier than tap water.
Reaction Experiment - Bobbing Raisins
Materials you will need:
• A Clear Glass/Jar
• Carbonated Drink (Clear)
• A Handful (4-6) of Raisins
Steps:
1. Pour the carbonated drink into the glass/jar.
2. Drop the raisins into the glass/jar.
What to see what happens to the raisins!!!
The bobbing up and down works because the bubbles of carbon dioxide gas in the drink are much less dense than the drink or the raisins.
Once the raisins start bobbing up and down, they will continue to rise and fall for about an hour.
-Raisins are denser than the carbonated drink, so they will sink.
-Gas bubbles attach to the wrinkles on the raisins.
-When the raisins are covered with the bubbles they become less dense than the drink, so they start to rise.
-The gas bubbles start bursting and then the raisins become denser than the drink, so they sink again.
Roll a Can With Static Electricity
An empty soda can
blown-up balloon
A head of hair
1. Place the can on its side on a flat smooth surface like a table or a smooth floor.
2. Rub the blown up balloon back and forth through your hair really fast.
3. Now the fun part - Hold the balloon close to the can without actually touching the can. The can will start to roll towards the balloon without you even touching it!
Try This Too: While you've got the balloon out, tear up part of a tissue into tiny pieces about 1/4 inch (.5 cm) big. Rub the balloon in your hair again and bring it close to the tissue pieces. They will be attracted to the balloon and then jump away.
When you rub the balloon through your hair, invisible electrons (with a negative charge) build up on the surface of the balloon. This is called static electricity, which means "non-moving electricity" The electrons have the power to pull very light objects (with a negative charge) toward them - like the soda can.
Bend Water with Static Electricity
A dry plastic comb (do not share combs from child to child)
An indoor faucet
A head full of clean dry hair.
1. Turn on the faucet and slowly turn down the water until you have a VERY thin stream of water flowing.
2. Take the plastic comb and brush it through your hair ten times.
3. Now slowly bring the comb close the the flowing water, (without actually touching the water) If all goes well, the stream of water should bend towards the comb! Magic you ask? Not really.
When you brushed that comb through your hair, tiny parts of the atoms in your hair, called ELECTRONS, collected on the comb. These electrons have a NEGATIVE charge. Remember that, it’s important. Now that the comb has a negative charge, it is attracted to things that have a POSITIVE charge. It is similar to the way some magnets are attracted to certain metals.
When you bring the negatively charged comb near the faucet it is attracted to the POSITIVE force of the water. The attraction is strong enough to actually pull the water towards the comb as it is flowing! If you want to try another experiment with your comb, tear up pieces of tissue until they are as a small as you can get them...I mean really small! Then charge your comb again by brushing it through your hair, and bring it close to the tiny pieces of tissue. If the pieces are small enough they will jump off the table to the comb the same way that the water was pulled to the comb. It is all thanks to the wonders of static electricity.
Lava Lamp
Materials:
A clean 1 liter clear soda bottle
3/4 cup of water
Vegetable Oil
Fizzing tablets (such as Alka Seltzer)
Food coloring
1. Pour the water into the bottle.
2. Use a measuring cup or funnel to slowly pour the vegetable oil into the bottle until it's almost full. You may have to wait a few minutes for the oil and water separate.
3. Add 10 drops of food coloring to the bottle (we like red, but any color will look great.) The drops will pass through the oil and then mix with the water below.
4. Break a seltzer tablet in half and drop the half tablet into the bottle. Watch it sink to the bottom and let the blobby greatness begin!
5. To keep the effect going, just add another tablet piece. For a true lava lamp effect, shine a flashlight through the bottom of the bottle.
To begin, the oil stays above the water because the oil is lighter than the water. The oil and water do not mix because of something called "intermolecular polarity." That term is fun to bring up in dinner conversation. When you added the tablet piece, it sank to the bottom and started dissolving and creating a gas. As the gas bubbles rose, they took some of the colored water with them. When the blob of water reached the top, the gas escaped and down went the water. Cool, huh? By the way, you can store your "Blobs in a Bottle" with the cap on, and then anytime you want to bring it back to life, just add another tablet piece.
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July 2009 Activity ideas obtained from ACES staff and public domain materials