motors!

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motors!

• (project science 2006)

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questions about motors
?

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

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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?

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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?

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KWL motors
K W L.

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how do motors work?
motors!

• (lets build one and find out.)

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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!

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motors!
how do motors work?

• (in theory)

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How motors work (1)http//electronics.howstuffwor
ks.com/motor1.htm

• An electric motor is allabout magnets
  andmagnetismA motor uses magnets tocreate
  motion
• you can see two magnetsin the motor The
  armature is an electromagnet, whilethe field
  magnet is apermanent magnet.

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How motors work (2)http//electronics.howstuffwor
ks.com/motor1.htm

• 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.

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How motors work (3)http//electronics.howstuffwor
ks.com/motor1.htm

• 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.

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How motors work (4)http//electronics.howstuffwor
ks.com/motor1.htm
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How motors work (5)http//electronics.howstuffwor
ks.com/motor1.htm

• The armature is an electromagnet made by coiling
  thin wire around a metal core.

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How motors work (6)http//electronics.howstuffwor
ks.com/motor1.htm

• flipping the electric field is accomplished by
  two parts the commutator and the brushes

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How motors work (7)http//electronics.howstuffwor
ks.com/motor1.htm

• 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.

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How motors work (8)http//electronics.howstuffwor
ks.com/motor1.htm

• 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 magnets north pole and attract
  the field magnets south pole.

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electromagnets
motors!

• (activity 2)