Data Sheet

Build the circuit, set the meter (M5) to the 5V scale, and turn on the slide
switch (S1). The meter measures the voltage across the white LED (D6)
and motor (M1). Notice how fast the fan spins, and how bright the lights
are. The lamps (L4) may be off.
Remove one lamp and compare the motor speed and brightness of the
lights. Then remove a second lamp and compare again.
Lastly, turn off the switch, remove the fan from the motor, then turn the
switch back on and compare the voltage measured and brightness of
the lights. Do this with one, two, or three lamps in the circuit.
Project 43
Motor & Lights
5V
+
The electromagnet (M3) has
a lot more resistance than the
lamps (L4).
Modify the preceding circuit to be this one. Keep the meter (M5) on the
5V scale. Turn on the slide switch (S1), then push the press switch (S2)
if the white LED (D6) is off or the motor (M1) is not spinning. Compare
the results to the preceding circuit. Try it with and without the fan on the
motor.
Project 44
Slow Motor & Lights
5V
+
With three lamps, the current
through each may not be
high enough to make its fila-
ment hot enough to glow.
!
WARNING: Moving parts. Do not
touch the fan during operation.
!
WARNING: Do not
lean over the motor.
!
WARNING: Moving parts. Do not
touch the fan during operation.
!
WARNING: Do not
lean over the motor.
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