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Lab Report
II. Introduction
The hypothesis on which this experiment was based was that a homemade reverse-motor generator could generate enough electricity to power a hot plate. This generator uses an electric drill (it is the only source available that provides enough RPM to get decent results) to spin the armature, which is the part of the generator that moves. In this model, the armature is a nail with copper wire coiled around it. The two ends of the wire connect to two patches of copper flashing which act as the commutators (switches that periodically reverse the poles on the magnets) and are insulated from the armature. A tin can is used as the stator (the part of the generator that doesn’t move), and the two sets of three magnets which are used as the field magnets (the permanent magnets fastened to the case) are attached to it. The brushes (the parts of the generator that hook it up to what it’s powering) are made out of copper flashing as well and are passed through holes on both sides of the can. They are insulated from each other and the can. When the commutators make contact with the brushes, the electricity gets transferred into them, and the brushes can be connected to wires that bring the electricity to the device that needs powering.
In order to make this electricity usable, the wires would need to be connected to an AC/DC inverter. An inverter can change AC current into the DC current needed to power most electrical objects. AC stands for alternating current, and in AC current, the electrons constantly switch directions, creating an alternating flow. DC stands for direct current, and in DC current, the electrons flow steadily in one direction, making the electricity easier for most machines to use.
This whole configuration generates electricity in the first place because of electromagnetic induction. Electromagnetic induction happens when you move a wire through a magnetic field created by magnets around it, causing the wire to produce a current. When the wire moves in the magnetic field, the charge that is already on the wire is affected. The charge's potential energy increases. In science, this is called electromotive force, and it is measured in volts. This is basically electricity and can be used to power electrical devices.

III. Materials and Methods

• Tin can
• Copper wire
• A nail
• Copper flashing
• Electrical tape
• Duct tape
• 6 magnets
• Wood
• A drill

First, take the tin can and punch two holes parallel to each other on either side of the can close to the bottom, leaving about half an inch of space from the end. Next cut the flashing into two 8-9” long strips and fold them in half so the cardboard side does not interfere with the brush to commutator connection. Cover the ends of the strips with electrical tape, leaving a little bit at one end of each exposed. Next thread the copper strips through the holes. Then drill a hole in the center of the bottom of the can, this will hold the end of the nail. Next wind the copper wire around the nail, leave the head exposed as well as about 2” of the other end of the nail. Next attach the magnets to the can, with two magnets opposite each other on the inside. Then do the same thing on the outside with two double stacked magnets so they line up with the ones on the inside. Next you cut two strips of copper flashing and accordion fold them in 1 cm long rectangles, they should be somewhat thick, then super glue them to the nail. Then you attach the ends of the wire that you wrapped around the nail to the rectangles. Then stick the nail point first into the can in between the brushes throw the hole. After that you can get an appropriate sized block of wood and duct tape the can to it. Then take a smaller piece of wood and drill a hole in it just big enough so that the end of the nail can rest there and not fall out. Then you attach the drill to the back of the nail, turn it on, and it should be working.

IV. Results
In a non-official test run of the generator at 300 rpm, it managed to generate 0.4 volts. During the official test, it generated nearly nothing, around 0.002 volts. The machine ran well, but for some reason wouldn’t work.

V. Conclusion
The hypothesis for this experiment was wrong: you cannot power a hot plate with a homemade reverse-motor generator. The design that this particular model was based off of is a good one and is very sound, and is even based off of the design of real generators, but it is not possible to build something like that at home using the simple materials that were available to us and with the little experience in such matters we have. This type of generator is very sensitive to a lot of factors, such as coil size, magnet configuration, the magnet’s proximity to the coils, number of magnets, material type, and the RPM of the armature. In order to work properly, the generator itself needs to be rather large compared to the size that was feasible to build in school so that all the components can be big enough to generate a lot of electricity (larger magnets create a larger magnetic field, and having more wire allows for more electromotive force to be created on the wires). The components also need to be built more precisely than was possible with the skills, tools, and materials available. There is a lot that could have been done with this model, the rpm on the armature is very slow compared to what it needs to be, and it’s much too small to generate enough. In order to get more power out of this homemade version, the best that could be done with what is known about these generators would just be to make it larger. If its size was increased by 5 or 10, its voltage could be increased as well. The armature could also be rotated faster, and the components could be better insulated from each other where necessary. Voltage very likely could have been lost into places they weren’t supposed to go because of gaps in insulation in various different locations (mainly where the brushes penetrate the can, where the armature goes through the can, and where the commutators attach to the armature.

Generator Description
A stationary-bike generator uses belts to transfer the energy generated by pedaling the bike into a more usable form of energy for powering electrical objects. They can be used one of two ways, either to cut out the electrical components of a mechanical device (ie. a washing machine) by using plain mechanical energy to directly power a mechanical object. Or to make electrical energy and create electricity to run a mechanical device's mechanical components off of. The plan for this project is to use the stationary bike to generate electrical energy.

In using a stationary bike to generate electricity for a hot plate to run off of without a battery, the rotation of the free-spinning wheel of the bike is used to turn a belt that can turn smaller series of gears until the gears that are being worked with are a reasonable size. These are used to spin a coil of copper wire in the middle of a circle of two or three stationary magnets. This creates electricity which can then be transferred to an electrical object using two wires. This is different from a conventional battery-run motor because this uses its motion in a different way, in effect, becoming a generator. The copper wire acts as an armature, the part of the motor that moves, and will be wound around a ferrous (iron based) material axle, the center point of the motor around which it rotates. There will be two sets of magnets, the field magnets on the inside of the steel stator (the stationary part of the motor, seen as the metal, cylindrical casing on toy motors), and one set on the outside of the stator. The brushes, in theory, should be copper, the brushes being the part of the motor that hook the battery up to the commutator in a conventional motor. (I say in theory because these may or may not be too difficult to construct so that they work properly, in which something else will have to be devised.) In this motor, the brushes will connect the armature with the outer set of magnets, and run along the steel casing.

In another variation of the same idea, the copper wire could remain stationary, and the magnets and casing could rotate around it. This would eliminate the need for brushes.
In order to get the electricity this generates to the device it will need to power, two wires will be connected to the copper wire and connected to either the hot plate directly, or an inverter or some such device that will make it more manageable (if one is available). An inverter will change the DC voltage to the AC voltage the hot plate needs in order to be able to run off of the generator.

This whole configuration generates electricity in the first place because of electromagnetic induction. Electromagnetic induction is when you move a wire through a magnetic field created by magnets, causing the wire to produce a current. When the wire moves in the magnetic field, the charge that is already on the wire is affected. The charge's potential energy increases. In science, this is called electromotive force, and it is measured in volts. This can be used to power electrical devices.

The information about how to make a bike powered generator came from and The information about how to set up the generator came from my dad. The information about why it works came from

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