Electricity and Magnets Study Guide
Electricity
 An electrical current is the flow of electrons.
 A closed circuit has all connections and lets the electrons flow
without interruption. There are at least 3 connections.
 An open circuit does not let the electrons flow. There is some
interruption of flow.
 A battery stores energy and has two ends, one positive and one
negative. Electrons flow from the negative end of the battery
through a wire to a switch or a bulb then back to the positive end of
the battery.
 A series circuit is wired in a complete circle, or path, positive to
negative. The advantages of a series circuit are that when you add
more volts the bulb is brighter. The disadvantages are that when
one bulb or battery is removed the circuit becomes open and the
bulbs go out. A second disadvantage is that the batteries don’t last
as long as in a parallel circuit.
 A parallel circuit is wired in separate paths. Batteries are
connected positive to positive ends and negative to negative ends.
The advantages of parallel circuits are that if one battery or bulb is
removed the circuit will stay closed. Another advantage is that the
batteries will last longer. The disadvantages of a parallel circuit are
that the bulb is not as bright and you have to use more wires.
 An insulator is a material that does not allow an electric current to
flow easily. Ex. plastic, rubber, paper, glass
 A conductor is a material that does allow an electric current to flow
easily. Ex. metal, copper, aluminum
 Static electricity have electrons that do not move but still create
an electrical charge.
Magnets
 Like poles repel.
 Opposite poles attract.