SCIENTIST. Do These: And Do Six of These:

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1 SCIENTIST Do These: 1. Read Bernoulli's Principle. Show how it works. 2. Read Pascal's Law. Tell about some inventions that use Pascal's law. 3. Read Newton's first law of motion. Show in three different ways how inertia works. 4. While you are a Webelos Scout, earn the Cub Scout Academics belt loop for Science. And Do Six of These: 5. Show the effects of atmospheric pressure. 6. Show the effects of air pressure. 7. Show the effects of water pressure. This may be combined with atmospheric pressure or with air pressure. 8. With adult supervision, build and launch a model rocket. (NOTE: You must be at least 10 years old to work with a model rocket kit sold in stores.) Describe how Newton's third law of motion explains how the rocket is propelled into the sky. 9. Explain what causes fog. Show how this works. 10. Explain how crystals are formed. Make some. 11. Explain how you use your center of gravity to keep your balance. Show three different balancing tricks. 12. Show in three different ways how your eyes work together, and show what is meant by an optical illusion. 13. While you are a Webelos Scout, earn the Cub Scout Academics belt loop for Weather. 14. While you are a Webelos Scout, earn the Cub Scout Academics belt loop for Astronomy.

2 Bernoulli's principle, physical principle formulated by Daniel Bernoulli that states that as the speed of a moving fluid (liquid or gas) increases, the pressure within the fluid decreases. Pascal's law (also known as Pascal's principle) is the statement that in a fluid at rest in a closed container, a pressure change in one part is transmitted without loss to every portion of the fluid and to the walls of the container. Newton s First Law: An object at rest will remain at rest unless acted on by an unbalanced force. An object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This law is often called "the law of inertia".

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4 Cub Scout Science requirements Belt Loop Requirements Complete these three requirements: 1. Explain the scientific method to your adult partner. 2. Use the scientific method in a simple science project. Explain the results to an adult. 3. Visit a museum, a laboratory, an observatory, a zoo, an aquarium, or other facility that employs scientists. Talk to a scientist about his or her work. Academics Pin Requirements Earn the Science belt loop, and complete five of the following requirements: 1. Make a simple electric motor that works. 2. Find a stream or other area that shows signs of erosion. Try to discover the cause of the erosion. 3. Plant seeds. Grow a flower, garden vegetable, or other plant. 4. Use these simple machines to accomplish tasks: lever, pulley, wheel-and-axle, wedge, inclined plane, and screw. 5. Learn about solids, liquids, and gases using just water. Freeze water until it turns into ice. Then, with an adult heat the ice until it turns back into a liquid and eventually boils and becomes a gas. 6. Build models of two atoms and two molecules, using plastic foam balls or other objects. 7. Make a collection of igneous, metamorphic, and sedimentary rocks and label them. 8. Learn about a creature that lives in the ocean. Share what you have learned with your den or family. 9. Label a drawing or diagram of the bones of the human skeleton. 10. Make a model or poster of the solar system. Label the planets and the sun. 11. Do a scientific experiment in front of an audience. Explain your results. 12. Read a book about a science subject that interests you.

5 Cub Scout Weather requirements Belt Loop Requirements Complete these three requirements: 1. Make a poster that shows and explains the water cycle. 2. Set up a simple weather station to record rainfall, temperature, air pressure, or evaporation for one week. 3. Watch the weather forecast on a local television station. Academics Pin Requirements Earn the Weather belt loop, and complete five of the following requirements: 1. Define the following terms: weather, humidity, precipitation, temperature, and wind. 2. Explain how clouds are made. Describe the different kinds of clouds-stratus, cumulus, cumulonimbus, and cirrus-and what kind of weather can be associated with these cloud types. 3. Describe the climate in your state. Compare its climate with that in another state. 4. Describe a potentially dangerous weather condition in your community. Discuss safety precautions and procedures for dealing with this condition. 5. Define what is meant by acid rain. Explain the greenhouse effect. 6. Talk to a meteorologist about his or her job. Learn about careers in meteorology. 7. Make a weather map of your state or country, using several weather symbols. 8. Explain the differences between tornadoes and hurricanes. 9. Make a simple weather vane. Make a list of other weather instruments and describe what they do. 10. Explain how weather can affect agriculture and the growing of food. 11. Make a report to your den or family on a book about weather. 12. Explain how rainbows are formed and then draw and color a rainbow.

6 MAKE YOUR OWN BAROMETER II MATERIALS: glass mayonnaise or canning jar balloon straw toothpick glue index card PROCESS: Stretch a piece of balloon over the glass jar. Glue a straw sideways from the center of the balloon to the end of the jar. Glue a toothpick to the end of the straw. On an index card write High on top and Low on the bottom near the toothpick's point. Watch and see what happens. EXPLANATION: Barometers keep track of air pressure. When air pressure is high (which means fair weather), the toothpick will point up because air will be pressing down on the balloon. When air pressure is low (which means stormy weather is coming), the toothpick will point down because air inside the jar will be pushing up against the balloon.

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8 Inquiry activity: Save the Ocean This is a problem solving exercise for a small group of 2-4 scouts. Materials: plastic dishpan of water, four 1-inch stones, drinking straw for each scout, plastic icecube tray, lead weights, water-proof putty Preparation: Set the stones in the dishpan. Put some putty in the icecube tray and press weights into it. Submerge in the dishpan. Add weight until it sinks but will float if upside down with air in the compartments. Sink the icecube tray and then position it upside down on top of the four stones. Place the straws on the table. The Problem: A large ship carrying very dangerous cargo has sunk off the coast. Your team has been called in to recover the ship and prevent its cargo from polluting the environment. Unfortunately, the ship is damaged and ropes will break it in half and it is resting nearly on the bottom so floats can not be slipped under it. Save that Ship! As the scouts tackle the problem, answer their questions about the rules and encourage them to discuss the problem and ideas they come up with. If they want a hint, ask them: "Why is the ship on the bottom?" (it is heavier than water.) "Is there some way to make it less heavy?" (displace water with air) "These are air hoses that can take air to the bottom of the ocean."

9 Air Flow Experiements Experiments: 1. Paper Strip Experiment Cut a piece of paper 2" by 6". Hold the narrow end, with the other end hanging down, in front of your mouth and blow across the top. Most people think the paper should go down as you blow across the top but surprisingly the paper rises up. 2. Ping-Pong Balls Experiment You need: 2 Ping-Pong balls, two 12" pieces of string, tape, and a ruler. a. Tape one end of the string to the Ping-Pong ball and do the same on the second one. b. Tape the other ends of the strings to the ruler so that the Ping-Pong balls are hanging about 1" apart. c. Hold the ruler up so that the balls hang freely. d. Now, blow between the balls from a distance of about 3". The balls should pull toward each other. 3. Paper Wing Experiment Cut a 4" by a 8 1/2" piece of paper and fold it in half. Tape the narrow edge one inch from opposite edge so that a wing with a flat bottom and curved top is formed. Slip a ruler through the wing loop end opposite the taped end with the curved side up. Now, blow directly at the folded part. The wing should rise up. 4. The Ball and Funnel Challenge Materials: Ping-Pong balls, a few large funnels Experiment: Let the scouts know that it is time to have a little contest--you are going to see who can blow a Ping-Pong ball out of a funnel the easiest. All you must do is give a ball and funnel to each participating scout, have them place the ball in the funnel, and then try to blow the ball out as far as they can. The ball won't move! In order to blow the Ping-Pong ball out of the funnel, you must blow across the top of the funnel. This activity can also be done by hooking a blower hose to the end of the funnel in order to provide a constant blowing air supply. The funnel can then be held upside down, swung around, etc., and the ball still will not fly out! 5. Water Up a Straw Materials: a tall glass of water, drinking straws a. Place one straw into the glass of water, holding it upright and keeping the bottom of the straw just off the bottom of the glass. b. Next, blow a short, hard blast of air through the second straw, holding it so that it is perpendicular to the first straw and their ends are touching. Water will come spraying out of the first straw into the air. Egg in the Bottle Peel a hard-boiled eggs just before doing the demonstration..set a small piece of paper on fire and drop it into the bottle. Place the hard-boiled egg on top or the opening of the bottle, small end first. The egg will be pulled into the bottle after the heated air from the fire has contracted. (As the air was heated, it began to expand. When the fire was extinguished, the air began to cool and contract. The egg seals the bottle. There is less air in the bottle causing unequal pressure to occur between the air in the bottle and the air outside the bottle. The air pressure on the outside pushes the egg into the bottle equalizing the air pressure inside and outside the bottle. Air pushes on all surfaces that it touches. This push is called air pressure. Pascal s Law

10 "The pressure of a liquid or a gas like air is the same in every direction if the liquid is in a closed container. If you put more pressure on the top of the liquid or gas. the increased pressure will spread all over the container." 1. A good experiment to demonstrate air pressure is to take two plumber's force cups (plumber's friend) and force them firmly against each other so that some of the air is forced out from between them. Then have the boys try to pull them apart. 2. When you drink something with a straw, do you suck up the liquid? No! What happens is that the air pressure inside the straw is reduced, so that the air outside the straw forces the liquid up the straw. To prove this fill a pop bottle with water, put a straw into the bottle, and then seal the top of the bottle with clay, taking care that the straw is not bent or crimped. Have one of the boys try to suck the water out of the bottle. They can't do it! Remove the clay and have the boy put two straws into his mouth. Put one of the straws into the bottle of water and the other on the outside. Again he'll have no luck in sucking water out of the bottle. The second straw equalizes the air pressure! Place about 1/4 cup baking soda in a coke bottle and 1/4 cup vinegar into a balloon. Fit the top of the balloon over the top of the bottle, and flip the balloon so that the vinegar goes into the bottle. The gas formed from the mixture will blow the balloon, up so that it will stand upright on the bottle and expand with C02. For this next experiment you will need: A medicine dropper, a tall jar, well filled with water; a sheet of rubber which can be cut from a balloon; and a rubber band. Dip the medicine dropper in the water and fill it partly. Test the dropper in the jar - if it starts to sink, squeeze out a few drops until it finally floats with the top of the bulb almost submerged. Now, cap the jar with the sheet of rubber and fix the rubber band around the edges until the jar is airtight. Push the rubber down with your finger and the upright dropper will sink. Now relax your finger and the dropper will rise. You have prepared a device known as a 'Cartesian Diver'. The downward pressure on the rubber forces the water up into the bottom of the diver, compressing the air above it, producing the effects of sinking, suspension and floating, according to the degree of pressure applied. Inertia "Inertia is the tendency of a thing at rest to remain at rest and a thing in motion to continue the same straight line". Get a small stick about 10 inches in length and the diameter of a pencil. Fold a newspaper and place it near the edge of a table. Place the stick under the newspaper on the table and let about half he stick extend over the edge of the table. Strike the stick sharply with another stick. Inertia should cause the stick on the table to break into two parts. Get a fresh egg and a hard-boiled egg. Give each of them a spinning motion in a soup dish. Observe that the hard-boiled egg spins longer. The inertia of the fluid contents of the fresh egg brings it to rest sooner.

11 MATERIALS: MAKE FOG glass jar strainer water ice cubes PROCESS: Fill up the jar completely with hot water for about a minute. Pour out almost all the water, but leave about one inch in the jar. Put the strainer over the top of the jar. Place a few (3-4) ice cubes in the strainer. Watch what happens! EXPLANATION: The cold air from the ice cubes collides with the warm, moist air in the bottle causing the water to condense and forming an eerie fog.

12 Crystal Clear Materials Needed: Salt Sugar Epsom salts laundry detergent flakes 4 glass jars 4 spoons magnifying glass thread or thin string very hot water pencils paper clips food coloring 1. Fill ajar half full of very hot water. Stir in a cup or more of salt, a little at a time, until no more will dissolve. 2. Rub some salt onto apiece of string. Tie it around a pencil, tie a paper clip to the other end, and drop into the water. Lay the pencil across the jar. 3. Put the glass in a cool place where it wont be disturbed. Do not touch the jar or the pencil. Watch for a few days. 4. Repeat the process with Epsom salts, sugar, and laundry detergent flakes. Try adding a little food coloring to one of the solutions. What is happening: The salt dissolves in the hot water. But cold water cant hold as much salt in a dissolved form. So as the water cools, the salt forms again on the string.

13 Optical Illusion Materials: A sheet of paper about 11 inches long. What to do: Roll the paper into a tube one inch in diameter. Hold the tube to your right eye an place the side of your left hand against the middle of the tube, with your left palm directly toward your left eye. Keep both eyes open as you look through the tube and you will see through your left hand.

14 One empty 35mm plastic film canister and lid. These are getting harder to find, but stores that develop film should have some. (The white canisters work much better than the black ones do.) If you have trouble finding canisters, you can get them HERE. One fizzing antacid tablet (such as Alka-Seltzer - Get this from your parents) Water Safety goggles 1. Put on those safety goggles and head outside - no really, when this works, that film canister really flies! If you want to try the indoor version, do not turn the canister upside down in step 5.

15 2. Break the antacid tablet in half. 3. Remove the lid from the film canister and put a teaspoon (5 ml) of water into the canister. Do the next 2 steps quickly 4. Drop the tablet half into the canister and snap the cap onto the canister (make sure that it snaps on tightly.) 5. Quickly put the canister on the ground CAP SIDE DOWN and STEP BACK at least 2 meters. 6. About 10 seconds later, you will hear a POP! and the film canister will launch into the air! Caution: If it does not launch, wait at least 30 second before examining the canister. Usually the cap is not on tight enough and the build up of gas leaked out. There's nothing like a little rocket science to add some excitement to the day. When you add the water it starts to dissolve the alka-seltzer tablet. This creates a gas call carbon dioxide. As the carbon dioxide is being released, it creates pressure inside the film canister. The more gas that is made, the more pressure builds up until the cap it blasted down and the rocket is blasted up. This system of thrust is how a real rocket works whether it is in outer space or here in the earth's atmosphere. Of course, real rockets use rocket fuel. You can experiment controlling the rocket's path by adding fins and a nose cone that you can make out of paper. If you like this experiment, try the Exploding Lunch Bag. Be safe and have fun! The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions: 1. Does water temperature affect how fast the rocket launches? 2. Does the size of the tablet piece affect how long it takes for the rocket to launch? 3. Can the flight path be controlled by adding fins or a nosecone to the canister? 4. How much water in the canister will give the highest flight? 5. How much water will give the quickest launch?

16 The Magic Ketchup Experiment! You can make a pack of ketchup float and sink at your command while it's sealed inside a bottle! * A 1 liter plastic bottle * Ketchup pack from a fast food restaurant * Salt (using Kosher salt helps keep the water from becoming foggy) 1. Remove any labels from the bottle and fill it all the way to the top with water. 2. Add a ketchup pack to the bottle. 3. If the ketchup floats, you're all set - go to step 4. If the ketchup sinks in the bottle, go to step For the floating ketchup pack simply screw the cap on the bottle and squeeze the sides of the bottle hard. If the ketchup sinks when you squeeze it, and floats when you release it, congratulations, you're ready to show it off. If it does not sink when you squeeze it, try a different kind of ketchup pack or try a mustard or soy sauce pack. 5. If the ketchup pack sinks, add about 3 tablespoons (45 ml) of salt to the bottle. Cap it and shake it up until the salt dissolves. (Kosher salt will keep the water from getting too cloudy, although it will usually clear up over time if using regular table salt.) 6. Continue adding salt, a few tablespoons at a time until the ketchup is just barely floating to the top of the bottle. 7. Once it is consistently floating, make sure the bottle is filled to the top with water, and then cap it tightly. 8. Now squeeze the bottle. The magic ketchup should sink when you squeeze the bottle and float up when you release it. With some practice you can get it to stop in the middle of the bottle. This experiment is all about buoyancy and density. Buoyancy describes whether objects float or sink. This usually describes how things float in liquids, but it can also describe how things float or sink in and various gasses. Density deals with the amount of mass an object has. Adding salt to the water adjusted the water's density

17 to get the ketchup to float. Sound complicated? It is, but here's the basics on the ketchup demo...there is a little bubble inside of the ketchup packet. As we know bubbles float, and the bubble in the ketchup sometimes keeps the heavy packet from sinking. When you squeeze the bottle hard enough, you put pressure on the packet. That causes the bubble to get smaller and the entire packet to become MORE DENSE than the water around it and the packet sinks. When you release the pressure, the bubble expands, making the packet less dense (and more buoyant) and, alas, it floats back up. This demonstration is sometimes known as a CARTESIAN DIVER. The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions: 1. Do different food packs (ketchup, mustard, soy sauce) have the same density? 2. Does the temperature of the water affect the density of the ketchup packet? 3. Does the size of the bottle affect how much you have to squeeze to get the packet to sink?

18 One small empty plastic soda or water bottle 1/2 cup of vinegar Small balloon Baking soda Funnel or piece of paper 1. Carefully pour the vinegar into the bottle. 2. This is the tricky part: Loosen up the balloon by stretching it a few times and then use the funnel to fill it a bit more than half way with baking soda. If you don't have a funnel you can make one using the paper and some tape. 3. Now carefully put the neck of the balloon all the way over the neck of the bottle without letting any baking soda into the bottle. 4. Ready? Lift the balloon up so that the baking soda falls from the balloon into the bottle and mixes with the vinegar. Watch the fizz-inflator at work! The baking soda and the vinegar create an ACID-BASE reaction and the two chemicals work together to create a gas, (carbon dioxide) Gasses need a lot of room to spread out and the carbon dioxide starts to fill the bottle, and then moves into the balloon to inflate it.

19 The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions: 1. Does water temperature affect how fast the balloon fills up? 2. Does the size of the bottle affect how much the balloon fills? 3. Can the amount the balloon fills-up be controlled by the amount of vinegar or baking soda?

20 1 balloon (round ones will work, but the longer "airship" balloons work best) 1 long piece of kite string (about feet long) 1 plastic straw tape 1. Tie one end of the string to a chair, door knob, or other support. 2. Put the other end of the string through the straw. 3. Pull the string tight and tie it to another support in the room. 4. Blow up the balloon (but don't tie it.) Pinch the end of the balloon and tape the balloon to the straw as shown above. You're ready for launch. 5. Let go and watch the rocket fly! So how does it work? It's all about the air...and thrust. As the air rushes out of the balloon, it creates a forward motion called THRUST. Thrust is a pushing force created by energy. In the balloon experiment, our thrust comes from the energy of the balloon forcing the air out. Different sizes and shapes of balloon will create more or less thrust. In a real rocket, thrust is created by the force of burning rocket fuel as it blasts from the rockets engine - as the engines blast down, the rocket goes up!

21 The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions: 1. Does the shape of the balloon affect how far (or fast) the rocket travels? 2. Does the length of the straw affect how far (or fast) the rocket travels? 3. Does the type of string affect how far (or fast) the rocket travels? (try fishing line, nylon string, cotton string, etc.) 4. Does the angle of the string affect how far (or fast) the rocket travels?

22 I know, it's not exactly an experiment, but illusions are still cool. Illusions are images that use your EYES to confuse your BRAIN Take a look at this grid: Did you notice the small grayish dots between the black boxes. They are not part of the drawing - they were put there by your brain! Scientists call this "visual vibration." Basically it means that when you see patterns of black and white, your eye sometimes confuses the two and blends them into patterns of gray that you see here. You are seeing something that is not really there! This elephant is missing a leg...or is it? The artist confuses his viewer by changing they way our brain is used to seeing things. It seems the more you look at the elephant, the more confusing it gets.

23 Want to see the gears move? Look at the dot and then move your head towards the screen and away from it.

24 This uses visual vibrations to create a cool effect. Try moving your head close to, and then away from the screen. The fuzzy dots appear to move.

25 This simple line drawing is titled, "Mother, Father, and daughter" (Fisher, 1968) because it contains the faces of all three people in the title.how many faces can you find? Look at the dots in the center. Which one is bigger? Like many similar illusions, the dots are the same size...really!

26 It can be hard to tell because your eye uses the other dots to make a comparison. Check out the spiral...except it is not a spiral, just circles. Don't believe me? Use your finger to follow the fake spiral. The tilt of the boxes fools your brain into believing it is a spiral.

27 Hey, this is weird. It looks as though it's moving, but it's not. The shapes confuse the eye (really the brain) into believing that they are moving.

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29 Close your left eye and hold this page about 8-9 inches from your right eye. Look at the cross and slowly move the page forward and backward until the black circle disappears.