Elenco Snap Circuits SnapMicro ® I Standard - Manual (Page 6)

5
The Variable Resistor ‘RV’ is really a resistor with a wiper arm that can slide from one side
of the resistor to the other side. As the wiper moves toward either end, the resistance
between the wiper and that end is reduced.
The Swi tch ‘S1’ is equivalent to a zero Ohm resistor when it is ON, and an infinite Ohm
resistor when it is OFF.
The LED (Light Emitting Diode) ‘D1’
is similar to a check valve in series with a light. Most
diodes act similar to water pipe check valves and must be installed in the correct direction for current to
flow.
Consider the water pipe check valve shown on
the right. When the piston pushes water into
the pipe the check valve opens and water
flows as shown. When the piston tries to suck
water from the pipe the check valve closes and
no current flows through the check valve.
Light is produced whenever current flows
through the LED check valve. The stronger the
current in the LED, the brighter the light. If the
LED is installed with the + symbol connected
to the negative voltage or ground the current
cannot flow and the LED will be off.
The DC Motor
converts a DC voltage to a rotation. The direction of the rotation
depends on the polarity of the voltage.
+