The Science on Wheels Program
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Science, Technology, Engineering and Mathematics
The shows are designed to be consistement with the North
Carolina Course of Study and the National Standard for Science Education.
As much as possible we map the activities within a given show with these two
standards (National Scienc Content Standard). We
also made a deliberate effort to guage the activities with other activities
around the country. A wealth of information is given for the teacher and the
students to further their understanding the concepts of the activities. In
the following few paragraph, we summarize the contents of each activity.
List of Lessons and handson activities
[Angular Momentum][Balling Ball Pendulum][Cathode Ray Tube][Gyroscope][Holograms][Magdeburg Hemispheres]
[Parabolic Mirrors][Pendulum][Polarization][See-Saws][UVFuore scence][ Virtual Images][ Wave Interference]
The following are adopted from
[Newton's Laws][Banana hammer][Bernoulli Ball][.Charges and interactions][Liquid Nitrogen and Balloons][Plasma
[Soap Suds Explosion][Sound Waves: Sound][Van de Graaff: Electricity][Vortex Generator]
Action-Reaction: Newton’s Laws
Materials:, Long Balloon, blown up; but not tied, Volunteer, Fire Extinguisher
Blue Cart, Plastic Stool
- Sir Isaac Newton was a brilliant scientist who lived about 300
years ago (1642-1727).
- He figured out three important rules about how things move.
- Newton’s third law says that forces always come in pairs where
each of the two forces are equal in size and point in opposite directions.
If you are pushing on something, it pushes back on you the same amount.
- When you lean against your friend, you both feel the same sized force
and the force each of you feels is acting in opposite directions.
- When someone shoots a rifle, the force of the exploding gunpowder
pushes the bullet out the end of the barrel, and an equal force, acting in
the opposite direction, pushes back against the rifle which gets shoved back
against the shoulder of the shooter called recoil).
- When you let the balloon go, it pushes the air out the back of the
balloon, so the balloon moves the other way. Like the balloon, the
fire extinguisher pushes air out in one direction, so the fire extinguisher,
the cart, and the rider go in the other direction.
Banana Hammer: States of Matter
2 Bananas, balsa wood board, a nail, Liquid Nitrogen, cryo gloves, crucible
- A banana is mostly made of water. Water is a liquid.
- The room temperature banana is too soft and mushy to hammer in a nail.
Imagine trying to hammer in a nail with a water balloon.
- Freezing the water in the banana is one way to make it a better
- The water molecules in the banana start to slow down when you make
- They start holding onto each other more tightly, like the volunteers
in the earlier demo.
- When the molecules get cold enough, the water in the banana becomes
a solid (ice).
- With a frozen banana, the nail can easily be hammered because the
solid water is much more rigid and tough than the liquid.
Leaf blower, NERF soccer ball/inflatable beach ball, Extension cord, Toilet
paper attachment for leaf blower, Toilet paper, Sheet of loose-leaf
- Air that moves fast in one direction doesn’t push as hard in the other
directions as air that’s standing still. (i.e. fast moving air in the x-direction
exerts less pressure in the y and z-directions.) So let’s say you have a
stream of air moving along… if you put an air pressure gauge next to it,
it would read less pressure than one on the other side of the room.
- Using your mouth to force air over the top of the sheet of paper lowers
the air pressure above the paper compared to the unmoving air underneath.
The difference in pressure forces the sheet of paper up.
- Using the leaf blower to force air over the top of the ball lowers
the air pressure above the ball compared to the unmoving air underneath.
The still air underneath the ball pushing upwards is enough to counteract
the downward pull of gravity.
- This effect is a part of what makes airplanes fly, and many schools
use this effect to explain flight. While the Bernoulli Effect is real and
it does play a role for certain types of planes, in general it’s a fairly
small contribution, and for many planes it isn’t even necessary.
Charges and interactions
Two red hats, One blue hat, Two voluteers
- Electricity is made up of two opposite kinds of charges (officially
called positive and negative). It doesn’t matter what you call them, the
important part is that they are opposite. We'll can call them Red and Blue
since we have hats of these colors.
- Like charges repel. Opposite charges attract
Liquid Nitrogen and Balloons: States of Matter
Liquid Nitrogen in 25L dewar, Big stainless steel dewar, Blue cryo gloves,
Balloon (long ones work better for this than round), Additional balloons or
balloon animals in the LN2 if you want., Purple balloon pump, Long crucible
tongs (optional, if you don't want to grab the balloons with the glove)
- Liquid Nitrogen is very cold (-320 degrees Fahrenheit, -195.82 degrees
- Nitrogen (gas) makes up most of the air we breathe (78% ).
- The balloon is full of air. Air is a gas.
- When you cool down a gas, the atoms start to slow down and hold on
to each other.
- When the atoms slow down enough, they start to be attracted to each
other. Eventually, they stick together and your gas turns into a liquid.
- A liquid takes up much less space than a gas.
- The air never leaves the balloon.
- When the atoms warm up, the liquid turns back into a gas.
Liquid Nitrogen Cannon: States of Matter
Liquid Nitrogen, Mallet to pound in cork (optional), Cork screw, for when
you pound the cork in too hard.
- The cannon is very warm compared to the LN2.
- When the LN2 is poured into the cannon, the cannon starts to warm
- When you heat a liquid it turns into a gas.
- Gases take up much more space than liquids.
- As it expands, the Nitrogen tries to take up more space, but the cork
is stopping it.
- After a second or so, the Nitrogen is pushing hard enough to pop the
Plasma Ball: Electricity
Plasma Ball, Fluorescent light bulb, Neon light tube, Rubber mat
or insulating stool
- A transformer collects (negative) charges on the small center sphere.
- Like charges repel. Opposite charges attract.
- The charges in the center want to get away from each other. They jump
off the sphere to get farther away from the other charges.
- The gas inside the Plasma Ball glows where the electricity passes
through the air.
- The charges are trying to go where there is no built up charge.
- The sphere builds up charge really fast because it’s small. The earth
is REALLY big so you can pour charges into it forever and they’ll never build
- • Charges always take the shortest, easiest path.
- If your friend lives next door, you wouldn’t walk around the block
just to go to their house. It would be easier to just walk straight there.
- Now if someone puts up a really tall fence between your two houses,
then climbing over it might be a SHORTER path, but it’s probably EASIER to
just walk around it. This is important: “shortest path” doesn’t always mean
distance. “Easier path” is more accurate.
- If the charges are given an easy enough path to the earth, they will
ALL go that way (instead of spreading out all over the Plasma Ball and traveling
through the air).
- When you touch your hand to the surface, the electricity flows from
the Plasma Ball through your body, down to the ground (earth)
Green and red lasers in stand, Prism, Screen or blank wall (not too far away),
Slide projector, Slide with narrow slit
- Different colors of light bend different amounts.
- Some shapes and materials (i.e. polyester resin prism) show this better
- White light is made up of all the different colors.
Racquetball: States of Matter
2 racquetballs (drop one into the LN2 right away), Liquid Nitrogen, cryo
- Racquetballs are solid.
- Even though they are solid, the molecules can flex a little, like
the people in our first demo when they were a solid.
- Freezing a racquetball causes the molecules to hold on tighter than
- The racquetball isn’t flexible anymore.
- When you try to make something bend that isn’t flexible anymore, it
- Even if the racquetball doesn’t break right away it won’t bounce as
Soap Suds Explosion: States of Matter (Finale)
Big stainless steel dewar, 2-3 Tbsp liquid dishsoap, diluted with water,
Food coloring, if desired, 2 gallon plastic bucket with 2-3 liters of warm
water, 10’ x 12’ plastic tarp, Blue cryo gloves, Safety glasses
- The water in the bucket is much warmer than the LN2.
- When the LN2 is dumped into the bucket, it warms up.
- When you heat a liquid, it turns into a gas.
- Gases take up much more space than liquids.
- When a lot of Nitrogen is warmed up really fast, it suddenly takes
up a lot of space.
- The soap lets us see the Nitrogen gas because it makes bubbles.
- The more Nitrogen or soap we use, the more bubbles we get.
Sound Waves: Sound
Lissajous Generator, Tripod, P.A. speaker, Keyboard
- Sound is made by vibrations (things moving).
- When things vibrate, they move the air molecules.
- The vibrating molecules bump into the ones close to them, which makes
them vibrate too. This keeps going until the vibrations reach your ear.
- When the air molecules bump into your eardrums you hear the sound.
- When the vibrations are fast, it sounds like a high note.
- When the vibrations are slow, it sounds like a low note.
- Inside the Lissajous generator is a laser and mirrors that can move
- When the Lissajous generator hears a sound, it makes the mirrors move
- you what the vibrations would LOOK like, if you could see them.Tablecloth
Van de Graaff: Electricity
Van de Graaff generator, Foot pedal switch, Grounding rod (handle and ball),
Rubbermaid stool, Aluminum charging rod
- The Van de Graaff separates the two kinds of charges from each other.
- A conveyor belt picks up charges from the base and puts them on the
- One kind of charge (positive) is on the large collector, and the other
(negative) is on the grounding ball.
- Opposite charges attract.
- The opposite charges want to get together so much that they will even
jump through the air to do it.
- If someone is touching the dome, the charge collects on them too.
The charge spreads out all over them, including onto their hair.
- Since each hair is covered with the same kind of charge, each hair
wants to get away from the others.
Vortex Generator: Air
2’ x 2’x 2’ clear polycarbonate Vortex Generator, Wood framed rubber sheet
for back of Vortex Generator, Candle and matches, Fog machine (with
fog fluid), Aluminized Mylar sheet, Spot light (optional)
- The so-called vortex generator is simply an empty box with a round
opening in the front and a rubber sheet for the back.
- Pushing the rubber sheet forces air out the hole in the front of the
- A vortex is a bunch of air or water that is swirling around itself.
Tornadoes and whirlpools are good examples.
- When the air is forced out the front of the generator, some hits the
edges of the hole and slows down. This slower air is then pulled forward
by the faster moving air in the center and starts swirling around itself
in a ring.
- The vortex can travel a large distance before breaking up if the air
in the room is calm.