Elenco Snap Circuits SnapMicro I Deluxe ® - Manual (Page 5)

4
ELECTRONIC COMPONENTS
First, consider voltage to be pressure on electrons to make them move in a wire. This is similar to water
pressure in a pipe to make the water move. For voltage we will use the symbol ‘V’ (volts).
Next consider the movement of electrons in a wire to be similar to the water moving in a water pipe. This
movement of electrons (or water) is called current and is represented by the symbol ‘I’ and measured in
units called amperes or amps.
Finally, let the friction of the wire (or water pipe) that tries to stop the current from flowing be called
resistance. For resistance we will use the letter ‘R’ or the Greek symbol (Ohm).
The ‘# Space Connector’ is really a wire or water pipe with close to zero resistance to
current flow. The # represents the number of bumps on the grid will be shorted. For example, a ‘3 Space
Connector’ covers 2 spaces and shorts (allows current to flow easily between) 3 bumps.
The Resistor limits the flow of current. The more resistance, the less current will flow at
the same pressure applied. For example, if a 10,000 Ohm or 10k resistor is placed across a 4.5 volt
battery less current will flow through it than if a 1k was placed across the same battery. To help
understand this principal, consider the following;
A water pipe filled with rocks would offer some
resistance to the flow of water.
A water pipe filled with sand would offer a greater
resistance to the water flow.
Water pipes filled only with water provide almost zero
resistance to the flow of water.
Most of the current will take the path
of least resistance as shown here.