Elenco Electronics 202 - Manual (Page 39)

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Project #61
OBJECTIVE: To learn about the speaker.
Speaker Static
Project #62
Parallel Resistors
OBJECTIVE: To learn about resistors.
Project #63
Series Resistors
Turn on either or both switches
(S1 & S2) and compare the LED
(D1) brightness.
This circuit has the 100 Ω
resistor (R1) and 1K Ω resistor
(R2) arranged in parallel. You
can see that the smaller 100
Ω
resistor controls the brightness
in this arrangement.
Turn on either or both switches
(S1 & S2) and compare the LED
(D1) brightness.
This circuit has the 100 Ω
resistor (R1), the 1K Ω resistor
(R2), and the photoresistor (RP)
arranged in series. You can see
that the larger photoresistor
controls the brightness in this
arrangement (the resistance of
the photoresistor will be much
higher than the others, unless
the light is very bright).
OBJECTIVE: To learn about resistors.
Turn the slide switch (S1) on and off several times. You hear static
from the speaker (SP) when you first turn on the switch, but hear
nothing after it is left on.
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.