Elenco Circuit Maker Skill Builder 125 - Manual (Page 19)

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Project #15
Project #16 Lift Loss
Build the circuit to the left.
Cover the photoresistor (RP) and turn on the slide switch (S1). The
motor (M1) should spin. If not, give it a push to get it started. Now
uncover the photoresistor or get a flashlight and shine it on the
photoresistor. The motor will slow down as more light reaches the
photoresistor, and will stop spinning if enough light reaches the
photoresistor. This circuit demonstrates how darkness can be used to
control a fan. Try this circuit with and without the fan on the motor.
Mumbling Motor
!
WARNING: Moving parts. Do not touch the
fan or motor during operation.
+
Place the fan on the motor (M1). Press the press switch (S2) and listen
to the motor. Why does the motor make sound?
If you replace the motor with the 2.5V lamp (L1), then it will work the
same as the “Hear the Motor” project, but only make noise when the
lamp is turned ON or OFF.
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 (SP) converts into sound.
!
WARNING: Moving parts. Do not touch the
fan or motor during operation.
CM-125_Manual_031514.qxp_CM-125_Manual_031514 4/2/14 12:19 PM Page 19