Elenco Snap Circuits® Home Learning - Manual (Page 41)

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Motor - a device which converts elecricity into mechanical motion. Electricity is closely related to magnetism, and an electric
current flowing in a wire has a magnetic field similar to that of a very, very tiny magnet. Inside the motor is three coils of wire
with many loops. If a large electric current flows through the loops the magnetic effects become concentrated enough to move
the coils. The motor has a magnet on a shaft so, as the electricity moves coils to align them with the permanent magnet, the
shaft spins.
Parallel circuit - a circuit with a number of separate paths for electricity to flow through.
Resistance - anything that opposes the flow of electricity in a circuit. The wires in a circuit provide some resistance, as do
lamps, motors, speakers, LED's, transistors, and integrated circuits. It is expressed in ohms.
Semiconductor - a material, usually silicon, which only lets some electrons flow through it.
Series circuit - a circuit with only one path for electricity to flow through. All of the parts in a series
circuit are connected one after the other. The light bulbs in a series circuit become dim as more lights are
added. When resistance increases, current decreases.
Terminals - the point where connections are made to an electrical device. For example, a
dry cell has two terminals. One is positive and the other is negative.
Transistor - a device which either amplifies an electronic signal, or switches current on and off. Transistors found
in computers and most electronic devices act as switches. One computer chip can hold millions of transistors.
Voltage - a measure of how strong an electric charge between materials is. It can be thought of as the electrical
pressure pushing electric current through a circuit. It is expressed in volts.