Project 30
Turn on the slide switch
(S1). If the shaft on the
motor
(M1)
isn’t
spinning, then give it a
push to get started.
Listen to the motor.
You can also try this
circuit with the glow fan
on the motor.
Hear the Motor
Project 31
Turn on the slide switch (S1),
and look at the brightness of the
color LED (D8). If the shaft on
the motor (M1) isn’t spinning,
then give it a push to get
started. Try it three ways: with
no fan on the motor, with the
glow fan on the motor, and
keeping the motor from
spinning with your fingers.
When the motor is spinning,
you will hear noise from the
speaker (SP).
Hear the Motor with Light
Why does the motor make
sound? A motor uses
magnetism
to
convert
electrical
energy
into
mechanical spinning motion.
As the motor shaft spins
around
it
connects/
disconnects several sets of
electrical contacts to give the
best magnetic properties. As
these contacts are switched,
an electrical disturbance is
created, which the speaker
The motor needs a lot of electricity to start
spinning, but needs less the faster it is
spinning. When kept from spinning by your
fingers, the motor sucks up all the
electricity, leaving none to light the color
LED. With the fan on the motor, the LED
gets enough electricity to light. When the
motor is spinning without the fan, the LED
gets more electricity and is brighter.
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