Project 61
Motor-Controlled Sounds
Project 62
Spin &
Shoot
Project 63
Spin Out
Siren
Project 64
Whirl Out
Warning
Project 65
Turn a
Tune
This project shows how a motor can be
used to convert mechanical energy to
electrical energy and sound. The
speaker uses electromagnetism to
create changes in air pressure, which
your ears feel and interpret as sound.
Think of the speaker as creating
pressure waves in the air just like
waves in a pool. You only see waves in
the pool when you disturb the water, so
the speaker only makes sound when
the voltage changes.
This circuit is controlled by spinning the motor (M1) with your
hands. Turn on the switch. A police siren is heard and then stops.
Spin the motor and it will play again. Note, however, that music
can be heard faintly in the background of the siren.
Modify the last circuit by
connecting points X & Y with the
2.5V lamp (L1). The circuit works
the same way but now it sounds
like a machine gun.
Now remove the connection
between X & Y and then make a
connection between T & U with
the 2.5V lamp (L1). The circuit
works the same way but now it
sounds like a fire engine.
Now remove the connection
between T & U and then make a
connection between U & Z. The
circuit works the same way but
now it sounds like an ambulance.
Now remove the connections
between U & Z and between V &
W, then make a connection
between T & U. The circuit works
the same way but now it sounds
like a familiar song but with static.
-30-
T V
X
U
W
Y
Z
To Next Page
Loading...
