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STATION #6: Electrical and Mechanical Energy Electricity and magnetism are related to each other. A magnetic field can produce an electrical current, and vice versa. Two instruments, called a motor and a generator, take advantage of this fact. A hand-powered flashlight contains a generator. Electric motors are used in many applications, including fans, electronic toys and cell phones. Here we will examine how generators and motors work. Background To see how electricity and magnetism are connected, make a circuit as shown on the Electromagnet Circuit sheet. You have created an electromagnet. Press and hold the switch and move the compass in a circle near the electromagnet. Observe what happens. Release the switch and move the compass again. What do you notice? An electric current flowing in a wire has a tiny magnetic field. By looping a long wire into a coil, the tiny magnetic field is concentrated into a large one, able to attract magnetic objects. Part I. If we depress the handle of the flashlight, then the flashlight will _______________ because _______________. Hypothesis Procedure Discussion Conclusions Part II. If we connect a motor to a battery, the motor will _______________ because _________________. Part I. Hand-powered flashlight: generator a) Squeeze the handle to light up the flashlight. b) Look what happens inside the flashlight when you squeeze the handle. Note what type of energy you put in, and what transformations it goes through within the flashlight. Part II. Electric motor a) Examine the electric motor that has been taken apart. Identify the coil of wire on a shaft and the small magnets. b) Connect the whole motor to a battery using the cables. Observe what happens. c) Switch the clips to the opposite terminals of the battery. Note if anything is different. How are motion and electricity connected? What applications make use of this phenomenon? Part I. A generator converts ____________________ energy to____________________ energy. Part II. An electric motor converts ____________________ energy to____________________ energy. In both cases, energy is lost in the forms of _____________________________. Electromagnetism Use the electromagnet circuit to explore electromagnetism. • Can you decorate the Wooly Willy with the electromagnet? Extensions/ • Loop two paper clips together. Hold them near the magnet and Applications move them around to see the magnetic field. Are there places where the magnetic field is stronger or weaker? • Draw a diagram of the electromagnet and draw the magnetic field lines around it.