Electricity...

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Electricity...

• Understanding the movement of electrons

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Energy v Matter

• Q? Does electricity have mass or volume, is it a
  form of Matter?
• Can the mass of electricity be found, does an
  electrical charge occupy a certain amount of
  space?
• No, therefore electricity (like heat, light
  sound) is a form of energy - not matter.

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Energy vs Matter

• It is important to remember that electricity is
  form of energy not matter.
• Therefore, electricity is concerned with the
  behaviour of electrical energy (more than the
  movement of matter).

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Laws of Electrical Charges

• Oppositely charged objects attract.
• Similarly charged objects repel.
• Charged objects attract neutral objects.

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Atomic Theory Review

• The quantitative relationship between protons
  electrons determines the charge of a given
  material.
• A given substance is usually neutral because the
  number of electrons protons are the equal.

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Atomic Theory Review

• Different substances are made up of different
  kinds of atoms.
• Some atoms have a stronger hold on their
  electrons than others do.
• Therefore, when two different materials are
  rubbed together, the one with the strongest hold
  on its electrons will remove electrons from the
  other material.

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Atomic Theory Review

• The material which gains electrons becomes
  negatively charged while the material that losses
  electrons becomes positively charged.
• A static charge is an excess or deficit of
  electrons.

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Types of Electricity

• Static At rest - when electrical energy
  remains stationary in/ on a charged object.
• Current Flowing - the movement of electrical
  energy along a pathway or circuit.

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Static Electricity

• Induction process by which a charged object
  produces a charge in another object with out
  touching it.
• Conduction process by which a charged object
  produces a charge in another object by touching
  it.

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Electroscopes

• The Electroscope is a device that is used to test
  the presence and behaviour of a static charge.
• Pith ball Electroscope
• Metal Leaf Electroscope

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Current Electricity

• The movement of electrical energy along a
  pathway.
• A pathway for electrical energy is called a
  circuit. A circuit is closed when electricity is
  allowed to flow around it. When electricity is
  not allowed to flow around a circuit it is
  considered open.

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Circuits

• Series A circuit where there is only one path
  for electricity to flow. All of the devices on a
  series circuit share electrical energy.

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The Series Circuit

• Electrical devices are connected along one path.

• Voltage is shared between all devices.

• Amperage is not shared between the devices.

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Circuits

• Parallel here there is more than one path for
  energy to take. The electrical devices are
  independently connected therefore do not
  share electrical energy.

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The Parallel Circuit

• Electrical devices are connected along more than
  one path.

• Voltage is not shared between all devices.

• Amperage is shared between the devices.

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Voltage (V)

• In order for an object to move there must be a
  force applied to make it move.

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Voltage (V)

• As far as electricity is concerned the force that
  pushes electrons around a circuit is voltage.
• Voltage refers to the amount of push electrons
  have in a circuit.

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Current/ Amperage (I)

• Amperage (Amps) is the unit used to measure the
  flow of current in an electrical circuit.
• It refers to the number of electrons that pass a
  specific point in the circuit over a given time.

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Resistance (R)

• Refers to slowing, hindering or resisting the
  flow of electrical energy.

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Resistance (R)

• Resistance is used to turn electrical energy into
  another form of energy (heat, light, sound)
  through some kind of device.
• Examples toaster, door bell or stereo.

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Ohms Law (IV/R)

• The amount of current that will flow through a
  circuit depends directly upon the voltage
  resistance.
• The relationship between current, voltage
  resistance is known as Ohms Law.

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Electrical Efficiency