Transcript Electric Motors

Electric Motors
Electric Circuits
An electric circuit is an electrical
path that begins at a power
source and ends up back at the
power source.
The component that is being
powered by the source is called
the load.
If the circuit isn’t complete,
electrons will stop flowing, which
will turn off the electricity.
Direct Current (DC)
In a DC circuit, electrons flow in
one direction from the negative
terminal to the positive terminal.
Alternating Current (AC)
The electrons that flow in an AC
circuit alternate.
(In other words they go back and
forth)
Conductors & Insulators
Conductor - A material whose atoms
easily give up their outer electrons,
letting an electrical current flow easily
through the material
Insulator - A material whose atoms
hold their outer electrons tightly,
resisting the flow of electrical current
through the material
Electricity and Magnetism
Electricity flowing through a wire
creates a magnetic field around
the wire.
Electricity and Magnetism
A coil of wire that has an electric current
passed through it becomes an
electromagnet.
By having more coils (wraps) you increase
the magnetic field.
What do we know about magnets?
Opposite poles attract and like
poles repel.
Inside an electric motor these
attracting and repelling forces
create rotary motion.
Motors in your kitchen…
 The fan over the stove and in the microwave oven
 The disposal under the sink
 The blender
 The can opener
 The refrigerator - Two or three in fact: one for the
compressor, one for the fan inside the refrigerator, as
well as one in the icemaker
 The mixer
 The tape player in the answering machine
 Probably even the clock on the oven
http://electronics.howstuffworks.com/motor.htm
Motors in your basement or
garage …
The
The
The
The
The
The
The
washer
dryer
electric screwdriver
vacuum cleaner (Dustbuster or Shop Vac)
electric saw
electric drill
furnace blower
http://electronics.howstuffworks.com/motor.htm
Motors in your bathroom…
The
The
The
The
fan
electric toothbrush
hair dryer
electric razor
http://electronics.howstuffworks.com/motor.htm
Motors in your car….
Power windows (a motor in each window)
Power seats (up to seven motors per
seat)
Fans for the heater and the radiator
Windshield wipers
The starter motor
Electric radio antennas
http://electronics.howstuffworks.com/motor.htm
Other places too!
Several in the VCR and DVD player
Several in a CD player or tape deck
Many in a computer (each disk drive has two or
three, plus there's a fan or two)
Most toys that move have at least one motor
(including Tickle-me-Elmo for its vibrations)
Electric clocks
The garage door opener
Aquarium pumps
http://electronics.howstuffworks.com/motor.htm
HOMEWORK
Armed with your new knowledge of
electrical motors and the experience of
building one, you are going to use your
motor to teach someone else how it
works. Your lesson can be given to any
adult and must be completed _________
___________. Your “student” needs to
fill out the brief description of your lesson
on the sheet provided.