Unit 4 · 8 lessons
Principles & Applications of Electricity
Static charge and why electrons move, conductors and safety, circuits and the meters that measure them, Ohm's law, series and parallel circuits, electrical energy, power, cost and efficiency, and how Ontario generates, stores and saves electricity.
- 76 practice questions
- 68 flashcards
- 2 interactive lessons
Lessons
- 1Static ElectricityStatic electricity is electric charge that builds up on an object and stays there. It happens because electrons move from one object to another; protons stay put. Learn the laws of electric charges, the three ways to charge an object (friction, contact and induction), how to use the electrostatic series, and how an electroscope detects charge.9 questions
- 2Conductors, Insulators and GroundingConductors let electrons move through them easily because some of their electrons are free to drift; insulators hold their electrons tightly. Learn why metals conduct, where semiconductors fit, what grounding does, how lightning forms, and how grounded plugs, GFCI outlets and good habits keep you safe from electric discharges.8 questions
- 3Current Electricity and CircuitsCurrent electricity is charge moving steadily around a closed loop called a circuit. Learn the parts of a circuit and their symbols, the three key quantities (current, potential difference and resistance) with their symbols and SI units, how to connect ammeters and voltmeters, and the difference between conventional current and electron flow.9 questions
- 4Ohm's LawFor many conductors, the current is directly proportional to the potential difference across them, and the ratio of the two is the resistance. That relationship, Ohm's law, is written V = IR. Learn to rearrange it, use it with real numbers and units, read a graph of V against I, and apply it to real situations like heaters, short circuits and wet skin.Interactive10 questions
- 5Series and Parallel CircuitsLoads can be connected in series (one path) or in parallel (several branches). Learn the current, potential difference and resistance rules for each, use them with Ohm's law to find missing values, and explain what happens when a bulb is removed or a branch is added, including why homes are wired in parallel.Interactive10 questions
- 6Electrical Energy, Power and CostElectricity is the general name for the effects of electric charges; electrical energy is the energy that moving charges carry and that loads transform. Power is how fast that energy is transformed. Learn P = VI and E = Pt, why utilities measure energy in kilowatt-hours, how to calculate the cost of running an appliance, and how time-of-use pricing works in Ontario.10 questions
- 7Efficiency and Energy Transformations in DevicesEvery electrical device transforms electrical energy into other forms, some useful and some wasted (usually as thermal energy). Percent efficiency compares the useful output energy to the total input energy. Learn to calculate efficiency, read Sankey diagrams, compare common devices, and use ENERGY STAR and EnerGuide labels and heat pumps to save energy.10 questions
- 8Generating Electricity SustainablyMost power plants spin a turbine that turns a generator. Learn how generators work, where Ontario's electricity comes from, the benefits and challenges of nuclear, hydroelectric, natural gas, wind, solar and bioenergy, the impacts on communities near and far, emerging technologies like battery storage and smart grids, and how to build a plan of action to save energy.10 questions