Electricity

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• Electricity-
• Flow of electrons through a conductor
• Matter
• Anything that takes up space. Can be solid,
  liquid or a gas.
• Molecule- smallest portion matter can be broken
  into without changing its original form.
• Atoms- small particles that make up the elements.
  
• Consist of protons, neutrons, electrons

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Atom Make up

• proton - positive charge
• electron - negative charge
• neutron - no charge (neutral)

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Size of Atom ?
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Conductors

• Have 1-3 electrons in outer orbit, easily knocked
  out of orbit. Materials such as silver, copper,
  aluminum, gold make good conductors.

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Insulators or Non Conductors

• Insulators, 5 or more electrons in outer orbit,
  glass, ceramics, plastics, rubber, fiber,
  porcelain, paper and wood are common Insulators.
  Hard to knock the electrons out of orbit if they
  have a strong magnetic pull to the protons in the
  nucleus of the atom.

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Electron Theory

• Electrons will flow from where there are many to
  where there are few.
• The flow of electrons is caused by having an
  excess number in one area, shortage in another.

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Amperage

• Quantity or how many free electrons flow through
  a conductor. current flow is measured in
  amperes(amps).
• Label A
• mA milliamp or 1/1000 of an amp
• Measured with an ammeter

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Voltage (Electromotive Force, EMF)

• Pressure or amount of push behind the current
  flow, this pressure is known as voltage
• Voltage is measured in volts with a voltmeter.
  Label v
• Kv kilovolts or 1000 volts

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Resistance

• Caused by electrons bumping into other atoms, a
  poor conductor has greater resistance than a good
  conductor.
• Measured in ohms. Symbol is omega
• 4 things that affect resistance
• 1. Type of material
• 2. Length of wire
• 3. Width of wire
• 4. Temperature- heat increases it

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Circuit

• Something which has a beginning point an ending
  point, and a specific path to follow.

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Electrical Circuit

• Must have a power source
• A load (something to operate such as a light bulb
  or motor)
• Wiring for path of electron flow (conductor)
• Switch

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Ground

• Ground means to complete the circuit back to
  source of power.
• Ground symbol

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• Series circuit, only one path for current to flow
• Each component is dependent on the next in order
  to work.

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Ohms Law

• Amperes I -intensity
• Volts E -electromotive force
• Ohms R -resistance
• To find E I x R I E / R R E
  / I

E
I X R
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• Parallel circuit, more than one path for current
  to flow, current flows through all units at once
• Each component is independent from the next one.

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• Series parallel, combination of both circuits

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Circuit Problems

• Open circuit, wire is broken.
• Short to ground, wire is touching ground.
• Short to voltage, wire is touching a hot wire.
  Load device is on even though switch is off.
• High resistance, current is being slowed by
  corrosion or a poor connection.

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Circuit Faults
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• 1. Smallest particle without loosing composition.
• 2. What is a circuit?
• 3. Ohms Law states
• 4. How do you find the total resistance of a
  series circuit?
• 5. Using Ohms Law What is the amperage of a
  circuit if the blower motor has a resistance
  value of 4 ohms?
• Bonus
• Diagram and give 3 formulas for Ohms law

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Electromagnet

• Is a magnet that is created by using electricity.
• Wrap a wire around an iron core and run
  electricity through the wire.
• 3 ways to increase strength of magnetic field
• 1.) Use more loops of wire
• 2.) Use larger wire
• 3.) Run more electricity through the wire

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Magnetic Induction

• Using magnetism to create electricity.
• Passing a wire through a magnetic field will
  cause electrons to flow.
• 4 ways to increase the output or amount of
  electricity.
• 1.) Run more loops of wire through field.
• 2.) Run larger wire through field
• 3.) Run wire through field faster
• 4.) Create a stronger magnetic field.

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Fuse

• Protects a circuit against damage caused by a
  short circuit
• High current heats and melts the link, creating
  an open circuit
• Current stops flowing in the circuit

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Fuse
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Fuse Box

• Contains fuses for various circuits

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Fusible Link

• Small section of wire designed to burn in half
  when excess current is present in the circuit
• Often used as protection between the battery and
  main fuse box
• If a major wire is shorted, the fusible link will
  burn in half to prevent an electrical fire and
  further damage

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Circuit Breaker

• Performs the same function as a fuse
• Disconnects the power source from the circuit
  when current becomes too high
• Most breakers will reset when current returns to
  a normal level

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Circuit Breaker

• High current heats the bimetal strip, causing it
  to deform and open the contacts

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Relay

• Electrically operated switch
• Allows a small, low current dash switch to
  control another high current circuit from a
  distant point
• Allows very small wires to be used behind the
  dash, while large wires may be needed in the
  relay-operated circuit

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Relay

• Control circuit current flow creates a magnetic
  field that pulls the points closed

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