Elenco Circuit Maker Skill Builder 125 - Manual (Page 39)

Project #70 Pop On, Pop Off
Project #71
Little R Rules
Project #72
Big R Rules
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.
-38-
Turn the slide switch (S1) on and off several times. You hear static from
the speaker (SP) when you turn off the switch.
Turn on either or both switches
and compare the LED
brightness.
This circuit has the 100W and
1KW resistors (R1 and R2)
arranged in parallel. You can
see that the smaller 100W
resistor controls the brightness
in this arrangement.
Turn on either or both switches
and compare the LED
brightness.
This circuit has the 100W
resistor (R1), the 1KW resistor
(R2), and the photoresistor (RP)
arranged in series. You can see
that the larger photoresistor
limits the brightness in this
arrangement (the resistance of
the photoresistor will be much
higher than the others, unless
the light is very bright).
CM-125_Manual_031514.qxp_CM-125_Manual_031514 4/2/14 12:19 PM Page 39