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SCRIPT FORM - TR 130 – (for a 5 minute show)Final Ver. Producer: Jerome Ferro Show Title: Do Try This at Home. Date: 09/29/2015 Time Video Audio 6:00 Bars Tone 5:30 Slate 5:10 Countdown 5:00 Camera With tone Show Title super (key over opening shot) Lower 3rd super: host . Good morning and welcome to "Do try this at home".My name is Jerry Ferro and today I am going to build a simple electric motor known as a "Beakman's Motor" and explain the theory of operation. Have you ever played with magnets? If so, you are well on your way to understanding how simple electric motors work. Magnets produce a magnetic field with a north pole and a south pole. Like poles repel, opposite poles attract. . An electric motor uses these attracting and repelling properties of magnets to create motion. An electric motor contains two types of magnets; 1. A permanent magnet A magnet with a constant magnetic field.. and 2. A temporary magnet or electromagnet A magnet that needs electrical current to create a magnetic field.. In this project, I will use a permanent magnet and a temporary magnet. The temporary magnet can also be called an electromagnet. To make an electric motor, an electromagnet is placed on an axle so it can spin freely. It is then positioned within the magnetic field of a permanent magnet. When current is passed through the electromagnet, the resulting magnetic field interacts with the permanent magnetic field to create attracting and repelling forces. These forces push the electromagnet, which spins on its axle, and an electric motor is born. The method applied in this demonstration uses Newton's first law of motion , which states that, "an object in motion remains in motion unless acted upon by an outside force". This means that when the electromagnet is spinning, it will continue to coast through a rotation unless something stops it. If current is always flowing through the wire, the resulting pushes will oppose each other, and the coil might bounce back and forth, but it will not spin continuously. However, if we can make the current flow only half of the time, all the pushes are in the same direction. This means the coil is actively pushed one-half of each rotation while current is flowing, and "coasts" through the next half cycle while no current is flowing, until it comes around and receives the next push. This allows the motor to spin continuously. Key CG Materials This project demonstrates what happens when an electromagnet is placed in the path of the magnetic field of a permenant magnet. Materials: These specialty items can be purchased from the Science Buddies Store: Electric Motor and Generator kit (1). You will need these items from the kit: Magnet wire, enamel-coated, approximately 50 inches [120 cm]. Sandpaper, fine-grit Magnets (3) Compass (1) A dowel or other cylinder, 1/2 inch [1.3 cm] in diameter. Ruler or measuring tape Scissors Battery, AA cell (2) Tape electrical tape or masking From one end of the magnetic wire, measure about 1.6 inches (4 cm), and from that point onward, wind about 30 inches of magnetic wire around a cylinder . Cut the magnetic wire with the scissors, leaving about 1.6 inches (4 cm) free (uncoiled) at the other end. Key CG Figure1 The magnetic wire must be neatly and evenly coiled. If it is not, the weight may not be evenly distributed, making it difficult for the electromagnetic coil to rotate in the final motor setup. Try to ensure the loops are touching each other, always parallel to one another, as shown in Figure 1. A coil is formed by winding magnetic wire neatly around a cylinder. 1.6 inches of wire is left free on each end to create the axles. Key CG Figure2 Carefully slide the loops of magnetic wire off the cylinder. Your coil should look circular or square, as shown in Figure 2. In this graphic you can see two examples of neatly coiled wire, each forming an electromagnet. The electromagnet is a coil. Because all loops of wire are parallel, each loop will get the same push. Adding up all those pushes, or motions, creates the nice spinning movement of a motor. Key CG Figure3 Keep the loops bunched together to form a tight coil: Thread each free end of the magnetic wire through the loops of the coil in the 3 o'clock and 9 o'clock positions, as shown in Figure 3. You should knot the magnetic wire to help the coils stay tightly bunched. The free ends of the magnetic wire should form a straight imaginary line through the coil (the imaginary line connects the 3 o'clock and 9 o'clock positions and runs further along the free ends). The free ends will be the axle on which your electromagnet turns. Figure 3 is a drawing illustrating how the coil and the axle that it spins on look when formed. The magnetic wire is protected with an electrically insulating enamel coating. This enamel coating needs to be removed from both ends of the axles to create electrical contact between the left and right axles and their supports. Key CG Figure4 Put up Figure 4 Please The top part of this drawing shows how the axles should be stripped: on the right axle, only the top half of the coating should be removed; on the left axle, all the coating should be removed. Why do we strip the wire this way? Stripping the insulation allows electrical contact so electrical current will flow. Stripping off the top half of the insulating material on the right axle will provide a period of time when current can flow through the coil to create a temporary magnetic field and a period of time when current cannot flow, so no temporary magnetic field is created. When the bare copper of the axle is rotated downward, bare copper will be touching the axle support, and current will flow through the coil. As soon as current flows through the coil, it becomes an electromagnet, creating a temporary magnetic field. The temporary magnetic field will interact with the permanent magnetic field and give the wire a push. When the bare copper is rotated upward, insulated copper will be touching the axle support, and no current will flow through the coil. There will not be a temporary magnetic field. According to Newton's first law of motion, the coil will keep moving in the direction it already traveling, because no force is stopping it. As soon as the bare copper of the axle is rotated down again, current will flow and the coil will get a new push, making it continue to rotate. So far, I have discussed the electromagnet. Now I will attach the coil to the base constructed off camera so that current can flow through the coil. I insert each axle end into a loop of the axle support. The motor might well start running right away! This motor needs some fine-tuning: Adjust the axle supports so the axle is horizontal. Give the coil a few turns to make sure it can spin freely and does not rub against the magnet. Turn your coil 180 degrees, as maybe the uncoated side of the axle was facing up, not touching the axle support. Contact of the bare wire with the axle support will create an electrical connection and allow current to flow. CAM Key CG Credits SOC (standard out cue) Theme Music Fade to Black Fade out Music