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Physics Science Fair Project Idea

Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.

ELECTROMAGNET COILS USE UP ENERGY TO MAKE MAGNETISM? Not right.
Sustaining a magnetic field requires no energy. Coils only require energy to initially create a magnetic field. They also require energy to defeat electrical friction (resistance); to keep the charges from slowing down as they flow in wires. But if the resistance is removed, the magnetic field can exist continuously without any energy input. If electrically frictionless superconductive wire is used, a coil can be momentarily connected to an energy supply to create the field. Afterwards the power supply can be removed and both the current and the magnetic field will continue forever without further energy input.

VOLTAGE(under construction)
Science fair experiment ideas are found here.  These ideas on science fair experiments include making real compasses that work and tell north from south.  Another good science fair experiment is to make toy frogs jump with static electricity. Other science fair experiment ideas include making leaf rubbings and forecasting the weather. For more ideas on science fair experiments you can make stain glass windows and kaleidoscopes.  Another science fair experiment is to make a real flying saucer.  This is a hovercraft that will boggle your mind. Imagine a science fair experiment that results in a real moving object that you can ride.  Science fair experiments like this are exciting, and you can also learn what judges are looking for.  Now your science fair experiment may win a prize. 

ELECTRIC CHARGES ONLY FLOW ON THE SURFACES OF WIRES? Wrong.
During a Direct Current in a simple circuit, the flow of charges takes place throughout the whole wire. The flow is not just on the surface. If the level of current is very high, then the wire will become hot, and the current will heat up the inside of the wire as well as its surface. Thin hollow pipes make poor conductors; their electrical resistance is too high. To avoid overheating the metal we should use thick solid bars instead.

There is a persistent 'rumor' that electric current exists only on the surface of metals. This mistaken idea probably comes about through a misunderstanding of the nature of electric charge. After all, when electric charge is deposited onto a metal object, it distributes itself over the surface of the object. It makes sense that, since charge is only on the surface of metals, a flow of charge must take place only on the surface of metals, right? Unfortunately, the word "charge" refers to two different things. When electric charge is placed on a metal object, the added charge is just a drop in the bucket compared to the amount of charge already in the neutral metal. "Uncharged" wires contain an enormous amount of charge inside, even though they may have "zero charge" on average. Are you confused yet? Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.

All metals contain huge amounts of movable electrons. During an electric current it is these electrons which flow. However, each electron is near a proton, and so the metal is said to be "uncharged." In a wire, electric current is a flow of "uncharged charge". Weird but true. Now if we were to place EXTRA charge upon a wire, that would be like pouring a teacup into the ocean. The "water level" would rise a tiny bit. Yet extra charges on a wire create a very noticeable electrical imbalance (they attract lint, deflect electroscopes, make sparks, etc.)

It isn't so strange that we might accidentally assume that the extra charges are the only charges on the wire. Yet in reality, electric currents happen in the "ocean" of the wire, and the extra "teacup" on the surface has little effect on the charge flow. The charge flow (current) is not just on the surface, and the whole "ocean" flows.

A second source of misunderstandings: during high frequency AC, the electric current on the surface of a conductor is higher at the surface than it is within the bulk of the metal. This is called the "skin effect." It is not very important for thin household wires at 60Hz. Perhaps some people heard about the Skin Effect but did not realize that it only works for very thick wires or for high frequency AC. At extremely high frequencies, the current does flow as a "skin" on the surface of large wires. For circuits involving high-current and high-frequency such as radio transmitters, it makes sense to use copper pipes as conductors. All the charge flow is on the surface of the conductors. All the heating takes place on the surface, and not deep within the metal.

ELECTRIC CHARGES ARE INVISIBLE? No.
Electric charges are easily visible to human eyes, even though their motion is not. "Electricity" is not invisible! Never has been. When you look at a metal wire, you can see the charges of electricity which would flow during electric currents. They are silvery/metallic in color. They give metals their mirrorlike shine. Some metals have other colors as well, brass and copper for instance. Yet in all cases, the "metallic"-looking stuff is the metal's electrons. A dense crowd of electrons looks silvery; "electric fluid" is a silver liquid. And if metals weren't full of movable electrons, they wouldn't look metallic. Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science project ideas, be sure to click the link above. See our blueprints for a physics science project ideas.

During electric currents in metals, the atoms stay still, but the silvery electron-stuff flows slowly along. Unfortunately the human eye cannot see the electric flow. That's part of the reason that "electricity" is so mysterious. Think about it... in an aquarium full of water, you cannot see any water flowing unless there are bubbles or dirt being carried along. And whenever clean water is flowing through a transparent hose, you can't see any flow. Even if the water is flowing very fast, the water-filled hose just looks like an unmoving glass rod. Same with wires: there's no bubbles or dirt being carried along by the electric current, therefore you can't see anything moving. You can see the STUFF that flows, just as you can see the water in an aquarium, but you can't see any flowing stuff.

Even if human eyes could see single electrons, we still couldn't see an electrical flow since the current is extremely slow. Electrons in metals typically flow at a few centimeters per hour, even during high currents. That's slower than the minute hand on a clock! Electric currents OOZE along like silly-putty flowing across a tilted board.

Seeing imbalances in charge
Here's a separate topic... while the metallic-looking sea of charges in a metal is easily seen, IMBALANCES of charge are not. This get's confusing, since many books call imbalances of charge by the name "charge." They will tell you that charge is invisible, yet they really mean that charge-imbalances are invisible.

Wires contain enormous amounts of movable negative charge in the form of electrons, but they also contain positive charge in the form of protons within the metal atoms. If the number of protons and electrons are equal, don't they cancel out? Doesn't that mean that no charge exists? No. It means that no IMBALANCE of charge exists.

An "uncharged" wire is still full of charge, it still contains positive and negative charge in huge but equal quantities. The word "uncharged" doesn't mean "without charge," instead it means "without charge-imbalance." Yet even if there are more electrons than protons, or fewer electrons than protons, this imbalance is invisible. It's invisible because the greatest difference attainable is incredibly tiny when compared to the amount of charge that's already there. If an object is highly charged; even charged up to millions of volts, the extra charge is like a teacup poured into an ocean. The difference is far too small to be seen.

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ATOMS HAVE EQUAL NUMBERS OF ELECTRONS AND PROTONS? Not in conductors!
Students misunderstand how electric circuits work. One reason for this is that they think the electrons in a metal are trapped on individual metal atoms. They also think that an applied voltage is needed to "free" the electrons and to change metal into a conductor. They aren't aware that the "sea of electrons" exists inside metal all the time. I suspect that this is part of a more general misconception that all atoms in a material are always neutral. This is wrong because ALL CONDUCTORS contain charged, movable particles. The very definition of "conductor" is "a material which contains mobile charges." If all atoms were truely neutral, then conductors could not exist. Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project ideas is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project ideas.

For example, a metal is made of positively charged atoms immersed in a sea of loose electrons. Apply a voltage to a metal, and its electrons begin flowing. Salt water is full of positive and negative ions. Glowing gas (fluorescent lights, neon signs, sparks) is full of movable electrons and movable positive ions. These three are teh most common conductors, and they owe their conductivity to the presence of movable charged particles which occur naturally. Looking for a physics science fair project ideas? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project ideas is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.


A "CONDUCTOR" IS A MATERIAL WHICH ALLOWS CHARGE TO PASS THROUGH IT? Not exactly.
The scientist's definition of the word "conductor" is different than the one above, and the one above has problems. For example, a vacuum offers no barrier to flows of electric charges, yet vacuum is an insulator. Vacuum is NOTHING, so how can it act as a barrier to electric current? Also, there is a similar problem with air: electric charges placed into the air can easily move along, yet air is an insulator. Or look at salt water versus oil. Oil is an insulator, while salt water is a conductor, yet neither liquid is able to halt the flow of any charges which are placed into it. How can we straighten out this paradox? Easy: use the proper definition of the word "conductor."

BAD:
Conductor - a material which allows charges to pass through itself Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want good physics science project ideas, be sure to click the link above. See our blueprints for a physics science fair project idea.

BETTER:
Conductor - a material which can support an electric current

BEST:
Conductor - a material which contains movable electric charges Looking for physics science project ideas? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.


ANALOGY:
Conductor - like a pipe which is already full of water
Insulator - like a pipe with frozen liquid; a pipe plugged by ice

If we place a Potential Difference across either air or a vacuum, no electric current appears. This is sensible, since there are few movable charges in air or vacuum, so there can be no electric current. If we place a voltage across a piece of metal or across a puddle of salt water, an electric current will appear, since these substances are always full of movable charges, and therefore the "voltage pressure" causes the charges to flow. In metal, the outer electrons of the atoms are not bound upon individual atoms but instead can move through the material, and a voltage can drive these "liquid" electrons along. In salt water, the individual sodium ions and chloride ions are free to flow, and a voltage can push them so they flow as an electric current. If we stick our wires into oil, there will be no electric current, since oil does not contain movable charges.Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.

If we were to inject charges into a vacuum, then we WOULD have electric current in a vacuum. This is how CRT's and vacuum tubes work; electrons are forcibly injected into the empty space by a hot filament. However, think about it for a second: it's no longer a vacuum when it contains a cloud of electrons! :) Maybe we should change their name to "electron-cloud tubes" rather than "vacuum tubes", since the electron cloud is required before there can be any conductivity in the space between the plates. (But vacuum tubes already have another name, so this would just confuse things. They are called "hollow-state devices." As opposed to "solid state devices?" Nyuk nyuk.)

HUMID AIR IS CONDUCTIVE? Mistake.
Electrostatic experiments don't work very well under humid conditions. Some books state that the water vapor in the air makes the air conductive. Wrong. In reality the problem is caused by the liquid water that becomes adsorbed on surfaces of objects.

In order to make the air conductive, we'd have to fill it with movable charged particles. Evaporated water is not made of charged particles (ions,) instead it's made of neutral molecules, so the high humidity does not significantly affect the conductivity of the air. Even suspended water droplets (fog) does not significantly affect conductivity. For fog to be conductive, the individual droplets would have to posess an electric charge.

However, during humid conditions most insulators develop a surface layer of conductive water mixed with contaminants (including dissolved salts which makes this layer of water conductive.) If you find that you can't separate any charges by rubbing a balloon on your head, it's because the humid air has made the balloon and the hair very slightly damp. The air remains nonconductive, but surfaces of insulators become conductive when damp. Conductive surfaces don't separate any opposite charges when rubbed together. Cure this by warming them (drying them) with a blow-dryer. If a pair of insulators is sufficiently dry, it will "generate charge" even under very humid conditions. If conductive air were the culprit, this cure couldn't work.

8. LIGHTNING RODS DISCHARGE THE CLOUDS? Mistake.
UNDER CONSTRUCTION
Make a model "landscape", install some lightning rods on the tiny houses, then bring a "storm cloud" nearby: bring the metal sphere of a VandeGraaff Electrostatic generator over your small town. The strong electric charge on the sphere will vanish. Doesn't this prove that lightning rods can discharge a thunderstorm? Nope. Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.

The above demonstration was thought at one time to be accurate, and this old mistake is still in many books. In reality, lightning rods cannot remove the charge-imbalance from a thunderstorm. The scale of the typical demo is wrong. The stormcloud is a few miles up, and a few miles across, yet the lightning rod on the house is only a few feet tall. Therefore the metal-sphere "cloud" should be fairly large, and "Rod" should be far less than 1mm tall and attached to a wide metal ground plate.

The typical demonstration doesn't illustrate a lightning rod, it illustrates a 2000-ft radio tower or extremely tall office building.

Think about it: how can a tiny needle affect cubic kilometers of strong e-field? How could the relatively tiny current from a metal rod discharge a cloud that's over 1KM away. It can't! To do so, it would have to emit a hurricane wind made of ionized air. Unfortunately the lightning rod on your roof only emits about the same current as the needle in the model town: it emits a few microamperes. In other words, the scale model is not correct because the current coming from the needle is way too high. In order to be at the proper scale, the current would have to be hundreds of thosands of times smaller; too small to affect the VDG machine's charge.

"ELECTRICITY IS WEIGHTLESS? Nope.
If by 'electricity' we mean the electrons, then 'electricity' is not weightless. Take a copper wire for example. Each atom weights about 115,000 times larger than the weight of an electron. If each atom supplies one electron to the "electric fluid" sea, then that sea is very light, but it is not weightless. The flowing "electricity" weighs about a hundred thosand times less than the copper metal. It's like a low pressure gas rather than like a liquid (but never forget that a gas is still matter!) One KG of copper would contain about ten milligrams of the movable electron-stuff which can flow as an electric current.

THE "TWO FLUIDS" THEORY WAS DISPROVED? Not exactly.
In the early days of electrical science, researchers were sure that there were two kinds of electricity: "vitreous electricity" and "resinous electricity," later to be named positive and negative electricity. They imagined that these represented two kinds of "electric fluid" which were somehow created by rubbing various materials together. Ben Franklin proposed a different concept: he imagined that there was only one kind of electric fluid, positive electricity, and believed that "negative electricity" was simply a lack of electric fluid.Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.

Some scientists objected to Franklin's idea. They rightly pointed out that, if Franklin were correct, then matter itself must be made up of negative electricity, otherwise a rubber rod wouldn't become negative when Franklin's electric fluid was removed from it. They noticed that Franklin was not proposing a single kind of electric stuff. Instead Franklin was saying that two opposite kinds of electricity exist, but only one of them is a movable "fluid." The other kind would be solidly connected to the material of an object.

In hindsight we can see that Franklin was wrong. During electric currents in batteries, currents in salt water, or in human flesh, the electric current is a flow of both positive and negative ions moving in opposite directions. Two flows of "electricity" take place in the same conductor. In your brain and nervous system, electric current is a flow of positive and negative atoms going in opposite directions. During electric currents in neon signs, in sparks, lightning, etc., there is a flow of both positive ions and electrons. The same is true for liquid metals. And when two materials are rubbed together, sometimes positive or negative ions are transferred, and sometimes electrons are transferred. In Franklin's language, two electric fluids do indeed exist, and Franklin's "one fluid" theory is wrong.Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.

Franklin was somewhat correct about two things. He was right about electric current in solid (non-liquid) metals. During electric currents in wires, it's the negative "electric fluid" which flows along, while the positive stuff behaves as an "electric solid" and cannot flow. But melt the metal and this frees up the positive atoms so that they can flow too. ALso, Franklin was right in suspecting that, in some situations, "positive electricity" and "negative electricity" differ greatly in mass. Protons are about 1800 times heavier than electrons, and positive ions heavier still. But when electric current is a flow of ions alone, the negative and positive ions can be very similar in mass, or the negative ions can even be far heavier than the positive.

The complexity of electric charge was far greater than Franklin and his contemporaries knew. Franklin was right about metals, but he was wrong about conductivity in general. Modern science recognizes that positive particles can flow, and recognizes the existence of both positrons and electrons, therefore it rejects Franklin's "one fluid" theory of electricity.

STORM CLOUDS ARE ELECTRIFIED BY FRICTION? No.Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.

Some books claim that the separated charges in thunderstorms come about because the clouds rub against each other, or because the falling rain rubs against the air. This is not correct. In fact, the true explanation for storm electrification is unknown. There are several possible explanations, but none of them has yet been accepted by scientists, and all the theories have problems. Here's one current theory:
In a mixture of rain and half-melted hail, the ice and water become oppositely electrified through contact. The large hail then falls faster than the small raindrops and spray. Two large regions appear in the cloud, a lower one that's made of hail, and an upper one that's made of rain. These regions contain opposite imbalances of electric charge.
So, what caused the clouds to become electrified? Contact between dissimilar materials, followed by wide separation of those materials.

BEN FRANKLIN'S KITE WAS STRUCK BY LIGHTNING? Never happened!
Many people believe that Ben Franklin's kite was hit by a lightning bolt, and think that this was how he proved that lightning was electrical. A number of books and even some encyclopedias say the same thing. They are wrong. When lightning strikes a kite, the spreading electric currents in the ground can kill anyone standing nearby, to say nothing of the person holding the string! So what did Franklin actually do? He showed that a kite would collect a tiny bit of electric charge out of the sky during a thunderstorm. Electric leakage through the air caused his kite and string to become electrified and so the hairs on the twine stood outwards. Twine is slightly conductive, so the imbalanced charge spread to all parts of the kite string. Franklin used the twine to electrify a metal key, and tiny sparks could then be drawn from the key. (He used a metal object because sparks cannot be directly drawn from the twine, it's not conductive enough.) This suggested that some stormclouds carry strong electrical net-charge. It IMPLIED that lightning was just a large electric spark.

The common belief that Franklin easily survived a lightning strike is not just wrong, it is dangerous: it may convince kids that it's OK to duplicate the kite experiment as long as they "protect" themselves by holding a silk ribbon. Make no mistake, Franklin's experiment was extremely dangerous, and if lightning had actually hit his kite, he certainly would have been killed.

ELECTRICITY IS MADE OF ELECTRONS? Wrong.
It's true that electric current in metals is a flow of electrons. But there are many other conductors besides metals, and sometimes the currents are not caused by moving electrons. Electric currents can also appear in electrolytes or in plasma. When an electric current creates the glowing plasma within a neon sign, electrons flow in one direction, while positively charged ATOMS flow in the other. Yes, there is an electron flow in the glowing gas, but part of the total electric current is also made of moving atoms which flow the other way.

Electric currents in electrolytes (such as wet dirt and human flesh) are flows of electrified atoms. In electrolytes, no electrons are flowing at all. For example, when an electric current is passing through a battery, it is not made of moving electrons, it is made of moving atoms (ions), and each atom carries a charge imbalance. A similar thing happens when an electric current passes through the damp earth, through the ocean, or through your body. If you receive an electric shock, no electrons flowed inside you. These electric currents are flows of atoms. All the electric currents in your brain and nerves are composed of moving sodium and potassium atoms. No electrons! (MORE)Looking for a physics science fair project idea? You've come to the right spot. We have physics science project ideas that you can download immediately. One physics science fair project idea is related to electromagnets. Other physics science fair project ideas include voltage, charges, electricity and more. If you want a good physics science fair project idea, be sure to click the link above. See our blueprints for a physics science fair project idea.

physics science project ideas

 

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