Given the following items: wire, light bulb, & battery, think about how you can light the bulb.

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1 Light the Bulb! What You'll Do: Given the following items: wire, light bulb, & battery, think about how you can light the bulb. >>>>>>>>>Draw all the possible combinations that you can make with the bulb, the wire and the battery.???????which ones will light the bulb? Which ones won't????????were you correct on the last question? Examine the filament of the bulb closely. If you took a piece of wire like that out of the bulb, and ran electricity through it, it would instantly burn up. It is really thin wire, isn't it!? Picture the electrons flowing through the thick wire (plenty of room) Then, they get to the thin wire. It is like they are being "squeezed" at this point. This causes what is scientifically called high resistance: a measurement of how hard it is for the electrons to move through a conductor. What do the electrons do in response? To keep the idea simple: They take all their energy of moving around and put it into producing heat which in turn produces light. This is called incandescence. It's like people, if you pack them tightly into a small room, the room will get hot!???????do you think that there is air in the bulb? Why? There are two conditions that a circuit can be in. OPEN or CLOSED. If the circuit is closed, that means it is "on", and thus the electrons are flowing through the circuit. If the circuit is open, that means it is off. Think of it this way. If you take a wire in the circuit and cut it, you have just cut it OPEN. Electricity, unless it is of VERY high voltage, will not travel through the air. With an opening in the circuit, there is no electrical flow. So, what's the point? We really, really take light bulbs for granted. Most people don't know how they work, or how they are integrated into a circuit. Now you know.

2 Motor City Madness 1. Treat the items here with care and leave the magnet on the battery. 2. At this station, there is the simplest of all possible motors I have ever seen. This defines elegance in motion: Something is scientifically elegant when it gets the job done simply and clearly. 3. To make this motor work, simply place the wire rotor on the cradle that is made by the paper clips. Help the motor start by giving it a nudge. See if you can hold it so it keeps on going. A motor is a great example of the relationship that exists between electricity and magnetism. Note how a source of electricity and a magnet are both necessary parts of a motor. This relationship is so important, and the two concepts are so closely connected, that many phenomena we see fall under what scientists call electromagnetism. In the study of electromagnetism, there is a simple concept called the motor effect. (If you have done the station with the galvanometer and coil, then this discussion will make more sense.) The motor effect is this: If you take a coil of wire and you run a magnet through it, then the electrons in it are forced to move by the force the magnet exerts. You just generated electricity. You made electrons flow by moving a magnet. You can also do the same thing, but "in reverse": You can take a coil of wire, stick a magnet in it, attach a battery to it, and watch the magnet get moved. This is because the moving electrons in the wire create a magnetic field, which can attract or repel the magnet. So, what's the Point? This motor has a special kind of wire. The insulation around this wire is hard to see. **ask me for a better example** On one end of the coil, the insulation has been sandpapered off all the way around. See if you can find that end. On the opposite end, the insulation has been sandpapered off of only one half the wire. This is the key to why the motor works: When the electricity flows through the coil, a magnetic field is created, and this forces the coil to move towards the magnet. As it spins, the electricity flow is turned on and off. HOW? Remember the insulation and how it was sanded.? When the electricity is off, the inertia of the spinning coil keeps it in motion (You know, Newton's first Law). Then, the electricity turns back on and pulls the coil toward the magnet. The cycle continues..as long as there is electricity, the motor spins.

3 Bullet Train? (3 second rule) **Don't leave anything at this station on for more than 3 seconds!!! The items could get hot enough to burn you. At this station, there should be a small tube that has been wrapped with wire (a solenoid), a power supply, a nail, a coil of wire, and a compass. There are also a 2 magnetic field viewing tubes. 1. Compare the 2 magnetic viewing tubes one has a magnet inside one doesn t. The black stuff in the tubes is made of iron filings, which make a pattern which shows you that there is a field of force all around the magnet. Notice how the lines of force go to the poles on the magnet. 2. Take the coil and make it surround the compass. **pic on back** Run electricity through the coil.??????what happens, and why? What is the relationship between electricity and magnetism?? 3. Try turning the compass a different way and then turn on the electricity. Try reversing the polarity of the circuit. 4. Now, take the solenoid and put the nail into it, such that the nail is not all the way in. Run electricity through the solenoid. Observe. 5.?????Why does this happen???? 6. >>>>>List four devices that would (or could) use a solenoid. Bullet trains are not exactly solenoids, but they sure use they same principle. As discussed at the last station, electricity running through a wire creates an magnetic field. The force of this magnetic field can become greater and greater as you make more coils. The magnetic field caused the compass to move, and it was enough to make the nail shoot into the solenoid. High speed "bullet trains also are propelled by a magnetic force that is created by coiled wire under the tracks. The water valves on your clothes washing machine are opened and closed by solenoids.

4 AC/DC (BAG) At this station, there is a coil (not a squirming coil), a bar magnet, & a galvanometer. Be careful with the coil, it's kind of fragile. 1. Take the bar magnet and place it inside the coil. 2. Run the magnet back and forth inside the coil and observe the galvanometer. Part II: 1. Connect the hand-generator to the light bulb look! Light!!! 2. Connect the both hand generators to each other. Turn the crank. Now turn it the opposite way. A galvanometer is a device that not only measures if there is electrical current(flow of electrons), but it also measures the direction that the electrons are flowing.??????does the electrical flow direction have anything to do with the direction the magnet is moving? When magnets cause electrons to move (electricity) OR, when electricity causes magnets to move, this is known as the motor effect. How the magnet that generates the electricity moves effects whether or not you have AC(Alternating Current) or DC(Direct Current) electricity. With alternating current, the electrons do not flow in a loop, but they get wiggled back and forth. They are constantly changing their direction of flow. Your house plugs give you AC current, at 60 Hertz, or 60 flip-flops in direction every second. With direct current, you get a flow of electrons from the negative end of the power source (like a battery) to the positive end of the power source. That is why batteries have + and - signs. The current flows in a loop with DC, going from the negative end of the battery to the positive end. TRY THIS with the 9v battery and the galvanometer. Then reverse the poles. What happens?!??????which kind of electricity did you make with the magnet AC or DC???????How could you make DC with a magnet and a coil???????what types of devices produce DC current???????how do your observations of the generators speak to the motor effect?

5 Conduction, conduction, what's your function? At this station, you will find a whole bunch of different objects, a battery, wires, & a light bulb. 1. Take the objects and use them to close the circuit. 2. See if the bulb lights as a result. 3. Record your results on a data table A conductor is a material that allows electrons to flow through it. An insulator is a material that does not allow electrons to flow through it. A resistor is a material that lets electrons through it, but not all at once. A superconductor is a special material that allows electrons to flow through it without any resistance. This means none of the electrons are slowed down, and none of the electrical energy is lost in the form of heat. (Ever notice wires getting hot?) If you haven't, then feel the vacuum cleaner cord after the vacuum cleaner has been running. >>>>>List the materials you tested and specify if they are conductors, insulators, or resistors.??????in reality, are the conductors you tested truly "conductors"

6 Series and Parallel At this station, you'll find two different ways to hook up three light bulbs in a circuit. Use your book to figure out which circuit is series and which is parallel.??????what is "in series" on the series circuit???????what are parallel to each other on the parallel circuit? Turn on the switch on the series circuit. With it on, unscrew one of the light bulbs.?????what happens??????why? Turn on the switch on the parallel circuit. With it on, unscrew one of the light bulbs.?????what happens? Unscrew another light bulb.????what happens.??????why? >>>>>>>Sketch out how each circuit is set up.??????when would it be beneficial to have a circuit in series???????when would it be beneficial to have a circuit in parallel???????how many paths can the electrons take in a series circuit???????how many paths can the electrons take in this parallel circuit???????what do you think would happen to the brightness of the light bulbs if you added 3 more to either circuit, for a total of six? Why would this happen? If you want to get power to many parts of a circuit, you are not limited to only one way of connecting the wires. How you connect the wires does effect how the whole circuit acts, especially if a part of the circuit is open or closed

7 Rube's Paperclip Lifter **Don't leave anything at this station on for more than 5 seconds!!! You will short the circuit!!! At this station, you'll find some insulated wire, a power supply, a nail, and paperclips. You will make an electromagnet. Take the nail and wrap it with 5 turns of wire. Run electricity through this setup and see how many clips it lifts. Make a data table, with your independent and dependent variables shown. Now do 10 turns, see how many clips this lifts. Record Repeat the process with 15 turns, 20 turns, 25 etc. An electromagnet is a way to have a magnet that can be turned on and off. Regular magnets are always attracting magnetic material.?????where would it be useful to have a magnet that turns on and off? An electromagnet is really just a solenoid with a magnetic metal (iron, nickel or cobalt) inserted in its coils. This is another station that demonstrates that there is a connection between electricity and magnetism. You can use electricity to make a strong magnetic field, and you can also use a moving magnetic field to move electrons (make electricity).

8 What's going on under there? At this station, you will find a mystery circuit board, a battery, wire and a light bulb. 1. You are to use the light bulb as a continuity tester. (kon--tin--ooo-itty) Use it to test if you have a connection between buttons. If there is a connection, then you have continuity. 2. >>>>>>Draw the board boards. Draw lines to show which buttons on the board have continuity. 3. Be careful. These things seem easy. Don't be fooled. Double check your answers. Discuss this with your group. Electricians wiring old buildings sometimes run into old wires, or lose track of the ones that they are installing. If they want to safely test where the wire goes, without ripping the walls apart, they can test wires to see where they start and end. When a circuit has continuity it can let electrons flow through it. When the electrons are flowing, the circuit is a closed circuit. If there is a break in the wire, or a switch is off, then you have an open circuit.????suppose you wanted to make a continuity tester for a person who is blind. What changes would you make??

9 Electric Circus Vocab and Concepts To Know Spend 20 min and define these terms!!! 1. electromagnetism (magnet + wire = electric current & electric current + wire = magnetic field) 2. current 3. galvanometer 4. AC (alternating current) 5. DC (direct current) 6. motor effect 7. generator 8. solenoid 9. polarity 10. electromagnet 11. circuit 12. open circuit 13. closed circuit 14. series circuit 15. parallel circuit 16. continuity 17. conductor 18. insulator 19. insulation 20. resistance 21. resistor 22. filament 23. incandescent