motors! (project science 2006)

? questions about motors… what is a motor? why do people use motors? why learn about motors?

what do we know about motors? etymological –What words have motor in them? –Use motor in a sentence. technical –Are there natural motors, or are all motors made by people? –What materials are motors made of? –Why do people use motors?

What do motors have to do with science? what is science? are motors part of science? where would motors fit in grades 3-5 according to our state science framework? which of the 11 conceptual theme(s) in the framework might relate to motors?

KWL: motors KWL….

motors! how do motors work? (let’s build one and find out.)

Activity 1: Simple Electric Motor Using the materials provided by the teacher and the directions on the activity sheet, you will each make your own motor!

(in theory…) motors! how do motors work?

How motors work (1) “An electric motor is all about magnets and magnetism: A motor uses magnets to create motion… “you can see two magnets in the motor: The armature is an electromagnet, while the field magnet is a permanent magnet.”

How motors work (2) “…the north end of the electromagnet would be repelled from the north end of the horseshoe magnet and attracted to the south end of the horseshoe magnet. The south end of the electromagnet would be repelled in a similar way.”

How motors work (3) “The key to an electric motor is … that, at the moment that this half- turn of motion completes, the field of the electromagnet flips. …If the field of the electromagnet were flipped at precisely the right moment at the end of each half-turn of motion, the electric motor would spin freely.”

How motors work (4)

How motors work (5) “The armature is an electromagnet made by coiling thin wire around … a metal core.”

How motors work (6) “flipping the electric field is accomplished by two parts: the commutator and the brushes”

How motors work (7) “When you put all of these parts together, what you have is a complete electric motor. “In this figure, the armature winding has been left out so that it is easier to see the commutator in action.”

How motors work (8) “as the armature passes through the horizontal position, the poles of the electromagnet flip. “Because of the flip, the north pole of the electromagnet is always above the axle so it can repel the field magnet’s north pole and attract the field magnet’s south pole.”

motors! electromagnets (activity 2)