I took the Savvy Cyber Course, created by Stevens Institute of Technology. It was funded through the Alliance Plus grant awarded by the U.S. Dept. of Education and implemented by "Think Tank". Supportive funding was provided by Phoenix Urban Systematic Initiative and Nadaburg School District.
Science is fun.
Science is exciting. Let's jump in and have a ball.
Always
have an adult help you with your experiments.
We are
going to do some experiments and you can write about what happened.
Ready...Set...Go!
BUBBLE MIX RECIPES Recipes for bubble mix differ, partly because soap powders and detergents vary in strength. Experiment and figure out which ones work best for you. Here are some suggestions that may help:
Handmade Bubbles: Bubbles are globs of air or gas inside a hollow liquid ball. Soap bubbles are globs of air enclosed in a film of soapy water. You can make bubbles by blowing through a pipe or a ring dipped in soapsuds. You can do it with just your hand, too.
You
Need:2 tablespoons dishwashing liquid (30 mL)
1 cup of warm water
What to do: Gently stir the dishwashing liquid into the warm water. Curl your fingers and dip your hand in the soapy mixture. Blow into your curled hand.
What Happens: Bubbles
form.
BUBBLE BLOWERS:
You can make bubble blowers
from almost anything:
soda straws, clay pipe,
funnel, paper cup with end
removed, cut away plastic
bottle, and more!
CLOTHES HANGER BUBBLE BLOWER:
You need:
an uncoated wire hanger
a circular object, such
as thick crayon or frozen juice can
What to do:
Make a ring by untwisting the wire hanger and then wrapping a piece of
it around the can (or crayon). Slip the can out. Leave 3" or
4" (7-10cm) of straight wire for a handle. Then bend the rest of
the wire back and forth until it snaps, and you have your bubble wand.
Dip it in bubble mix and wave it in the air.
What happens: You get a spray of bubbles.
Why: By waving the
soapy wand in the air, you add the air that forms the center of the bubble.
SUPER BUBBLE:
To create a large bubble, you should use a large bubble blower and a strong bubble mix.
You need:
2 drinking straws (plastic work best)
a jar of strong bubble mix (see Bubble Recipes Section)
3 feet (90 cm) of string
a large baking pan
What to do: Thread the string through the two drinking straws and tie the ends of the string to one another. Pour the bubble mix into a large baking pan or tray. Wetting your fingers first, hold one straw in each hand and dip the strings and straws into the mixture for a couple of seconds. Remove the strings form the mix and pull the straws apart so that the string is taut (very tight). Holding the straws as though they were a frame, wave them around several times. then pull the straws upward and bring them close together.
What happens: You release an enormous round bubble.
Why: You get a large
bubble because you are adding a large amount of air when you wave the straw
frame and pull the straws up. As this air pushes out in all directions,
you pull apart the molecules of the soapy film. But the molecules
are attracted to one another, and the elastic skin of the bubble contracts
as much as it can to form the smallest surface for the air it contains.
The form that has the smallest surface is the sphere. That's why
the bubble is round.
BUBBLE DUET:
Blow 2 bubbles with one bubble blower - and see how they affect one another.
You Need:
a plastic drinking straw
scissors
a bowl of bubble mix
What to do: Cut four
slits about 2/3 " long (17 mm) at both ends of a plastic drinking straw.
Bend the cut strips outward. Make a small slit in the middle of the
straw, and bend it at the slit. You have now created a two ended
bubble pipe.
Dip one end of the pipe into the bubble mix and blow into the middle slit. You'll get a bubble. Blow a second bubble by dipping the other end of your pipe into the mix and blowing trough the middle slit again.
Then seal the slit in the middle of the bubble pipe by covering it with your fingers.
What happens: When you blow the second bubble, the first one gets larger. When the opening is sealed, the smaller second bubble gets even smaller while the first one gets even larger.
Why: Because a small bubble is more curved than a large bubble, the air pressure exerted by its "elastic" skin is greater than that on a large bubble. Therefore, the small bubble gets smaller. The air from it is forced into the bigger bubble, which then gets even larger.
BUBBLE STAND:
To make
a "stand" for your bubbles, all you need to do is place a plastic cup or
container upside down.
Or you
can place a pencil in the hole of a wooden spool of thread and wind a wire
loop around it.
Transfer
a bubble from a bubble blower to the stand by simply shaking it off gently.
You can then observe the bubble - and make others.
BUBBLE IN A BUBBLE IN A BUBBLE:
Use your bubble stand to put a bubble in your bubble's bubble.
You need: a plastic
cup (or other bubble stand)
bubble mix
a bubble ring (or other bubble blower)
a straw
What to do: Wet the top of a plastic cup or the wire loop of a bubble stand. Blow a large soap bubble with the wire ring and attach it to the bubble stand. Wet a plastic straw in the bubble mix and put it through the large bubble. Blow a smaller bubble inside the larger one. Then carefully push the straw through your smaller bubble, and blow an even smaller bubble.
What happens: You get a bubble in a bubble in a bubble.
Why: Anything wet
can penetrate the bubble without breaking it. The wet surface coming
into contact with the soapy film becomes part of it. Don't touch the wet
wall with your smaller bubble or you won't get a separate bubble.
WRITE ABOUT IT: Do you think there is a limit to how many bubbles
you can put inside a bubble? Why? How many did you get?
Compare your results to your friend's results.
PUTTING A BUBBLE TO WORK:
We can make an ordinary soap bubble do work for us!
You need: an empty
thread spool
a 3 inch square of paper (7.5cm)
a 1/2 inch cork (12 mm)
bubble mix
a long needle
What to do: Stick a needle through the cork, point up. Place the cork on a level surface. Fold the paper diagonally twice. Unfold it. Balance the center of the paper square (where the creases meet) on the point of the needle. Dip the spool in the bubble mix and blow a bubble on one end. Hold the other end toward the paper.
What happens: The paper moves.
Why: Air escaping from the bubble moves the paper.
SCIENTISTS OFTEN USE INSTRUMENTS TO HELP THEM WITH THEIR EXPERIMENTS.
LET'S MAKE SOME INSTRUMENTS
RIGHT NOW!!!
HOW TO MAKE A COMPASS:
A compass tells us which
direction is North.
You need: a needle
a magnet
a dish of water
a cork 1/4" to 1/2" thick (6 mm - 12 mm)
What to do: Magnetize the needle by stroking it at least 50 times in one direction with either pole of the magnet. Float the cork in the dish of water. Carefully center the needle on the cork.
WRITE
ABOUT IT: Write about what happened when you made your compass.
Make up a story that has your compass playing an important part in the
ending.
MAGNIFYING GLASS:
A magnifying glass made
out of water? Impossible?
You need: butter or
cooking oil
a paper clip or piece of wire hanger
water
telephone directory, newspaper or postage stamp
What to do: Straighten a paper clip or snip off a 4 inch (10 cm) piece of wire hanger by bending the wire back and forth a number of times. Form a small loop at one end of the wire and rub a little butter, margarine or cooking oil on it. Dip the loop into a glass of water and lift it out. You now have a lens - a sort of frame that holds a layer of water. Use the lens to read the small print in a telephone directory, the classified ads in a newspaper, or the fine details of a postage stamp.
What happens: The print is magnified.
Why: The water lens, just like a glass or plastic lens, has a definite shape. It bends light rays as they pass through it. First, it bends light as the light enters. Then it bends it again as the light leaves. The angle at which the water bends the light depends upon the shape of the lens. Reflected light spreads out from the object you are looking at, hits the lens, and is bent back to your eye. Your eye sees the light as though it came on a straight line from the object - and the object seems to be much larger than it actually is.
HOW MUCH BIGGER?
You
can find out just how much larger a lens makes an object by using a piece
of graph paper. You can also use ordinary typing paper, but you need
to draw graph lines on it. Look through your magnifying glass at
the lined paper. Count the number of lines you see through the "lens"
compared to the number you see outside of it. If there are 4 lines
outside compared to one inside, the lens magnifies 4 times.
WRITE
ABOUT IT: Imagine that you had to decode a very important message
that was written on a stamp. Tell how you did it, using only water,
oil and a paper clip.
WATER TRICKS
All light- from the sun,
from electric lights and from fires- usually travels in straight lines.
But light does strange things when it goes through the air and then through
water. Here are some ways to find out what it does.
THE MAGIC COIN
You need:
a small coin
a bowl (not see-through)
water
What to do & What happens: Drop a small coin into a china or plastic bowl. Tilt the bowl until you cannot quite see the coin over the edge. Hold the bowl in exactly the same position so you still cannot quite see the coin. Pour water slowly into the bowl and the coin will gradually reappear. Now hold the bowl up so you can see the coin. Move the bowl slowly up and down, staring at the coin. As you watch, it seems to move up and down in the bowl.
Why?: Light rays are
bent as they pass through water and then bend again as they (light rays)
leave water. This makes the coin "reappear" in the bowl.
BROKEN STRAW?
You need: glass
of water
straw (or pencil)
What to do & what will happen: Put a straw or pencil into a glass of water. Hold the glass up level with your eyes and the straw or pencil will look broken.
Why: Light going through
air and then through water at an angle, bends as it goes into water and
out again. This makes the straw or pencil appear to bend.
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to find out more. Click on one of the following links to ask some questions
or just explore.
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