Science Physics Electricity

• Static electricity - The build-up of an electric charge on the surface of an object. The charge remains in one area rather than flowing to another area
• Types of lightning

  • Ball Lightning
  • Sprite Lightning
  • Jet Lightning
• Science of Lightning

  1. Water particles move up in a storm cloud, transferring negative charges to downward moving particles

  2. Negative charges on the bottom of the storm cloud repel negative charges on the ground, making the ground positive

  3. Ground and storm cloud create an electric field

  4. Flow of positive and negative charges occur in the field, forming lightning
• Law of Electric Charges
• Lightning is an example of static electricity building up then discharging
• Charging by Friction

  Two neutral objects rub together. Electrons move to the objects with the stronger tendency to gain electrons. Both objects form opposite charges at the end of the electron transfer
• Static charges form on objects when electrons move. Protons do NOT move
• Charging by Induction

  This method uses three items: A charged object, A neutral object, A ground (a very large object with the ability to pick up excess electrons or to give up electrons without becoming charged). Another method utilizes two neutral objects and a charged object
• Charging by Conduction

  A charged object touches a neutral object. Electrons transfer to the object with fewer electrons. Both objects have the same charge as the charged object when they are moved apart
• Electrons move to the objects with the stronger tendency to gain electrons

  1. will move to the objects that are lower in the triboelectric series
• Methods of Charging

  1. Charging by friction

  2. Charging by conduction

  3. Charging by induction

  4. Electroscope
• Charging by contact


  When the bars and sphere are in contact, the electrons will spread out as they are now connected. Like charges repel and electrons are all negatively charged, as such, they repel one another. Electrons will be pushed from the bar to the sphere because it is less negatively charged. After the electrons have been evenly distributed, when the objects separate, their charges will be identical as a result. The electrons from the bar before and during the contact have now been distributed
• Short triboelectric series

  • hair
  • glass
  • silk
  • cotton
  • acrylic
  • rubber
  • polystyrene
  • PVC
• Charging methods

  1. Friction

  2. Conduction

  3. Induction
• Electrical Conductors


  • Electrons held loosely by atoms
  • Electrons DO move freely
  • Poor at holding static charge
  • Examples: metals (copper, silver, gold, etc)
• Charges on objects after charging

  • Opposite charges (higher in TS has + charge; lower in TS has – charge)
  • Same charge as the original charged object
  • Opposite charge as the original charged object
• Materials for charging methods

  • Two neutral objects
  • One charged object + one neutral object
  • One charged object + one neutral object + a ground
• Electrical Insulators


  • Electrons held tightly by atoms
  • Electrons do NOT move freely through the material
  • Good at holding STATIC charge
  • Examples: wood, wool, cotton, paper, rubber, plastic
• Electron movement

  1. Based on the triboelectric series (TS)

  2. Towards the object with fewer electrons (negative → neutral) (neutral → positive)

  3. Varies with the step in the process
• Terms related to static charge

  • Friction
  • Contact
  • Induction
  • Triboelectric series
  • Grounding
  • Electric discharge
  • Electrical conductor
  • Electrical insulator
  • Electrostatic
• Electricity is a form of energy resulting from the existence of charged particles (protons or electrons) either statically as an accumulation of charge or dynamically as a current
• Circuit


  • A closed (continuous) loop that carries electricity. It consists of an energy source (usually a battery), conducting wires and at least one load
  • Sometimes a switch is used to open and close the circuit
  • Electrons flow freely in conductors
• Constructing a circuit


  1. 1 battery, 3 wires (no load) = short circuit

  2. 1 battery, 3 wires, a light (load) = closed circuit
• Electric current


  The rate of electron flow past a certain point in a circuit. For any electrical device to operate there must be a flow of electrons. The symbol is "I" and the unit is amperes (A) or "amps"
• Electron flow direction


  Differs from conventional current flow direction
• Measuring current using an ammeter

  1. Ammeter measures current and displays it in amperes

  2. Ammeter can be moved to different locations around the circuit
• Circuit diagram


  • Uses standardized symbols to represent circuit components
  • Drawn with 90 degree corners and a ruler
• Circuit diagrams


  • Examples of drawing circuit diagrams for different circuits
• Some circuit diagrams will have bulbs that light up, others will not
• Read Chapter 11 - Static Electricity and add new information to your science notes
• Unit 3 - Physics
• 3.5 Series and Parallel Circuits
• Lesson 3.5 – Series and Parallel Circuit
• Lesson topics


  • Circuit
  • Series Circuit
  • Parallel Circuit
• Review Circuit Diagrams
• Circuit Diagram Symbols


  • Circuit
  • Series Circuit
  • Parallel Circuit
• PhET Activity (link)
• Series Circuit topics


  • Follow the instruction on the worksheet and complete the questions
  • What happens to the other bulbs if one of the light bulbs has been taken away or turned off?
• Parallel Circuit topics


  • What happens to the other bulbs if one of the light bulbs has been taken away or turned off?
  • Summary
  • Homework Practice
• Summary


  • Homework Practice