Datasheet-1

5V
+
Part B
5V
Project 41
Holding Down
!
WARNING: Moving parts. Do not
touch the fan during operation.
!
WARNING:
Do not lean over the motor.
Build the circuit. Set the meter (M5) to the 5V
scale, place the fan on the motor (M1), and drop
the thin rod into the electromagnet (M3).
Turn on the slide switch (S1). The fan spins, the
lamps (L4) light, and the meter measures the
voltage. Nothing happens to the thin rod. No-
tice that the voltage is much lower then the nor-
mal 4.5V; the motor and lamps are overloading
the batteries (B3), so the voltage drops.
Part B: Turn off the circuit, remove the motor
and lamps, then turn the circuit back on. Now
the measured voltage is much higher, and the
thin rod gets sucked up by the electromagnet.
The motor and lamps overloaded
the batteries and prevented the
electromagnet from sucking up
the thin rod.
How do you think the measured voltage in the top circuit would be affected if you added 100 more
lamps to the circuit?
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