Circuits

1
Circuits

• Chapter 11
• Lesson 8

2
Circuits

• A path along which charged particles can travel.
• In circuits electrons are charged particles that
  move through the wires and bulbs.
• Current is a flow of charged particles, such as
  electrons moving through a circuit.
• Batteries push a current of electrons through
  them.
• The crowded electrons at the negative end of the
  battery repel electrons in the wire, while the
  positive end of the battery pulls on the
  electrons
• Electrons begin moving from negative to positive
  through the wire devices.

3
Simple Circuits

• Simple circuits have a source of electricity,
  devices such as lamps, and connecting wires.
• When the wires are connected, the source of
  electricity starts pushing and pulling on the
  electrons in all parts of the wires and devices.

4
Resistors

• Current in a circuit is made smaller when a
  resistor is added to the path.
• A resistor opposes a flow of electrons.
• Resistor are added to circuits to control current.

5
Short Circuit

• A short circuit is a very conductive path that
  bypasses less conductive parts of a circuits.
• The current, in turn, heats the wire greatly.
• In many cases the heat can actually start fires.

6
Series vs. Parallel

• Series circuits A circuit in which there is
  only one path for the electric current.
• All series circuits share an important property
  the flow of charges is the same at any point.
• Some of the electrons begin pilling up in front
  of the resistors.
• Parallel circuits a circuit with more than one
  path for current.
• The current in each path of a parallel circuit
  depends on the strength of its resistor.
• The currents are added together to find the total
  current of the circuits.

7
Open vs. Closed

• Open Circuit a circuit that is incomplete.
• The battery in an open circuit can push a certain
  number of electrons onto the wire attached to its
  negative end.

• Closed Circuit a circuit has a complete path
  for current.
• The SWITCH allows you to open and close the
  circuit.
• In the on position, the switch closes a circuit
  in the off position, it opens the circuit.