EMF Investigation Essay Research Paper Planning Aim

EMF Investigation Essay, Research Paper

Planning Aim and hypotheses According to Fleming’s Rule, electricity is generated when movement occurs in the magnetic field. Alternatively, switching direction of the magnetic field also works. Alternating current is a good way of alternating the field direction. The electricity generated, of in the other words, the electromotive force, is measured in volts. By varying different parts of the apparatus, the EMF output could also vary. The aim of this investigation is to establish a connection between the factors and the output. Possible factors that could be altered in a general apparatus are: * Frequency of field alternation * No of coil of wire in the magnetic field * Strength of magnetic field, varied by * – size of electromagnet * – current used to establish and maintain the magnetism of the electromagnet * – no of coil used to magnetize the electromagnet * Moving the wire in the magnetic field A preliminary experiment, with the same apparatus used, is done earlier on and some useful information was acquired from it. As it was mentioned that alter the direction of the field generates electricity, and it was found out in the preliminary experiment that the more frequent that the field is altered, the quicker would electricity be generated, so by looking at different frequency, perhaps a pattern indicating the relation. In an experiment involving generating movement by electromagnet, the more wire coiled through the motor, the faster the movement would be. So in reverse, if more coil of wire is passed through the field, more electricity should be consequentially generated. Strength of electromagnet is also one of the three factors in the Left-Hand rule. Thus if the strength of the magnetic field is increased, more electricity should be generated. In the same way, more movement of the wire in the field should generate more EMF. The proof of this has also been acquired through the preliminary experiment. However, it was found out that the result in moving the wire in the field is too insignificant to record, so this factor could be undoubtedly omitted. Also no of coil used to magnetize the electromagnet contributes towards the strength of the magnet, it provides more area of magnetic field in the wire that magnetize the metal electromagnet. From the list, I choose to investigate into the effect of varying the frequency of the power alternating and strength of the electromagnet. Using a signal generator and varying the current passing through the electromagnet respectively could do this. The voltages that the power pack can supply are 0, 2, 4, 6, 8, 10 and 12 V. The maximum amps that it can go up to is 0.30A, so the exact current measurement has to neglected until the actual experiment itself, then it could be properly recorded and presented. As a criterion, the other factors have to be kept constant in order to make this a fair test. Here are the variations: 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100 Hz 0.025 – 0.30 Amps Ideally, all results should be repeated, and the average should be taken to obtain more accurate results. When carrying out the experiment, make sure that the factors are controlled strictly. Make sure that the current is the same, if necessary. Make sure that 240 coils of wire are being used. Make sure that the electromagnets are connected to each other firmly, if not, push them into each other. Make sure that frequency stays the same all the way through the experiment, and that there is only one loop of coil in the field at all the time. Planning Apparatus and Methods Equipment list * Green wire, stripped at both ends * Connector wires * Ammeter * AC power supply * 2 horse shoe metal * 120/ 240 coil of wire, magnetizing the horse shoe metal * Oscilloscope * Power lines * Signal generator Methods * Connect the circuit up as shown in the diagram. * Before any power is turned on, make sure the circuit is safe to use and is connected correctly. * Turn the power on. Adjust the voltage so that the current reading is correct. * Make sure that the control factors are the same. * Read the voltage reading on the oscilloscope. * Record the results. * Repeat the experiment necessarily, varying the factors as needed. Safety precaution * Dealing with electricity is dangerous. Take attentive cautions. * The horseshoe metal, when the power is passed onto them, could be dangerous as they rush into each other. Put them together before the power is turned on to prevent accidents. Prediction As the frequency of the AC current increases, more electricity should be generated. According to the trial experiment, the quicker the direction of the magnetic field alternates, more electricity is generated. So if the frequency of the change in direction is higher, more EMF should be generated. And as the current is increased through the unmagnetized-magnet, more electricity is generated. This is because the electric domains inside the magnet become magnetized. This is not a cumulative effect, so more energy is needed to magnetize more domains. The more domains magnetized, the stronger the electromagnet will become. Planning Background Knowledge Electromagnet is often a piece of metal in a coil of wire. When the wire has no current flowing through, the magnet is just a regular piece of metal that possesses no magnetic ability. However when the current is passed through, the metal becomes magnetized. This is because the wire is magnetized; thus the metal adj