1. Are the objective and introduction written in an engaging way? Yes No     If 'No' please explain. characters left 2. Is the difficulty level accurate? Yes No     If 'No' please explain. characters left 3. Were the materials easily obtained? Yes No     If 'No' please explain. characters left 4. Was the procedure clear? Yes No      If 'No' please explain. characters left 5. Were all safety measures included? Yes No      If 'No' please explain. characters left 6. Did you obtain clear, unambiguous results? Yes No     If 'No' please explain. characters left 7. How much time did you spend on the project? Choose One... A day or less Several days About one week A couple weeks Several weeks to months 8. How much did the project cost? Choose One... Less than $20 $20 - $50 $50 - $100 $100 - $150 $150+ Optional:  Do you have any suggestions to improve this project? characters left Optional:  Attach a picture of your project (JPG, JPEG, GIF, PNG only) Optional:  Caption for picture characters left Thank you for your feedback! * Note: This is an abbreviated project idea, without notes to start your background research or a procedure for how to do the experiment. You can identify abbreviated project ideas by the asterisk at the end of the title. If you want a project idea with full instructions, please pick one without an asterisk. Abstract An electric current produces a magnetic field. You can take advantage of this fact to make a simple apparatus to test the electrical conductivity of various materials, including both solids and liquids. The detector consists of a coil of wire, with a magnetic compass inside it. You connect one end of the coil to a D-cell battery. The other end of the coil is connected to whatever material you are testing, and the material, in turn, is connected to the other end of the D-cell. In other words, the coil is connected in series with whatever material you are testing. To make the coil, use about 10 m (33 feet) of insulated, 24 gauge wire. You can use a roll of duct tape (or something similar) as the form for wrapping the coil. Leave 30 cm (about a foot) of wire loose at each end of the coil for connecting it up to your circuit. Strip off about 1 cm of insulation from each end. Stand the coil on its side (you can prop it up with clay to keep it from rolling). Fold a piece of cardboard to make a platform for the magnetic compass at the center of the coil. Use insulated wires with alligator clips to connect the coil to the rest of your circuit. You can make connectors for a D-cell battery by taping a paper clip to each end and resting the battery on its side. To test conductivity of a liquid, use paper clips taped on opposite sides of a plastic cup as connectors. When testing different materials, connect the battery only long enough to see the compass needle movement, so the battery will last longer. Other ideas you can explore: Learn about the "right hand rule" for magnetic fields produced by electrical current. Does the compass needle move as expected according to the right hand rule? Learn about Ohm's law and try your detector in circuits with various resistors. Is there a relationship between how far the compass needle moves and the current flow in the circuit? (Math, 1981, 13; Gardner, 2004, 80–85) Bibliography Gardner, R., 2004. Electricity and Magnetism Science Fair Projects: Using Batteries, Balloons, and Other Hair-Raising Stuff. Berkeley Heights, NJ: Enslow Publishers. Math, I., 1981. Wires and Watts: Understanding and Using Electricity. New York, NY: Charles Scribner's Sons. Variations For more science project ideas in this area of science, see Electricity & Electronics Project Ideas. Last edit date: 2009-03-13 14:33:32

I Did This Project! Tell us about your experience with this science project. What was the most important thing you learned? characters left What problems did you encounter? (Enter "none" if you had none.) characters left Can you suggest any improvements or ideas? (Enter "no" if you have none.) characters left How do you rate this project? Poor OK Good Very Good Excellent Optional:  Attach a picture of your project (JPG, JPEG, GIF, PNG only) Optional:  Caption for picture characters left Thank you for your feedback! Related Links Science Fair Project Guide Project Summary Difficulty  6  Time required Short (several days) Share this Project Idea! Donate to Science Buddies Motorola Solutions Foundation sponsors Summer Science Camp Resource Summer Science Camp Resource

Career Focus

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	Electrician Electricians are the people who bring electricity to our homes, schools, businesses, public spaces, and streets—lighting up our world, keeping the indoor temperature comfortable, and powering TVs, computers, and all sorts of machines that make life better. Electricians install and maintain the wiring and equipment that carries electricity, and they also fix electrical machines.			Electrical & Electronics Engineer Just as a potter forms clay, or a steel worker molds molten steel, electrical and electronics engineers gather and shape electricity and use it to make products that transmit power or transmit information. Electrical and electronics engineers may specialize in one of the millions of products that make or use electricity, like cell phones, electric motors, microwaves, medical instruments, airline navigation system, or handheld games.
	Electrical Engineering Technician Electrical engineering technicians help design, test, and manufacture electrical and electronic equipment. These people are part of the team of engineers and research scientists that keep our high-tech world going and moving forward.

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