Datasheet-1

Magnet
Coil of Wire
Water Flow
Gears are used between two wheels or shafts. One wheel spins at
low speed but with great force, while the other wheel spins at high
speed but with much less force. This can increase efficiency or give
greater control.
Project 62
Make Your Own Generator
+
1mA
Build the circuit and set the
meter (M5) to the 1mA scale.
Spin the motor (M1) top clock-
wise with your fingers and watch
how much current is produced.
(Clockwise means in the direc-
tion in which the hands of a
clock rotate.)
Now spin the motor in the other
direction (counter-clockwise).
You won’t see much current pro-
duced now because it is pro-
duced in the other direction - the
meter needs to be flipped
around. Instead of flipping the
meter around, flip the motor
around to see this.
Name some products in your home that
have a generator.
This circuit is a true generator, using mo-
tion (and magnetism) to make an electric
current.In electric power plants, the same
thing happens but on a much larger scale.
High-pressure steam or water spins a
shaft, which uses magnetism to make an
electric current in a coil of wire.
Notice that this circuit used the 1mA
meter setting while the preceding circuit
used the 1A setting (1000 times greater).
You can produce a much higher current
by spinning the shaft much faster.
Hand-cranked generators like this are
used in some flashlights instead of batter-
ies. They use gears to spin the shaft
much faster.
Project 61 Motor with Flashes
Build the circuit shown and watch the white
LED (D6) as you push and release the
press switch (S2). Notice that even though
the LED is connected backwards, it is flash-
ing dimly while the fan is spinning, and then
flashes brightly when you release the press
switch.
You can also try this without the fan, or hold-
ing the motor top so it can’t spin (but don’t
touch the motor top while it is spinning).
!
WARNING: Moving parts. Do not
touch the fan during operation.
As the motor shafts spins it pro-
duces small voltage spikes (both
positive and negative), which can
be enough to dimly light the LED.
When you release the switch (turn-
ing off power to the motor), a mag-
netic field in it collapses, releasing
energy that lights the white LED.
+
!
WARNING:
Do not lean over the motor.
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