Report Card Descriptors
• Developing understanding of simple circuits
• Applies understanding of circuits to construction/control of motorized devices

Capacitors
• Word Document For This Study
• Capacitors are electricity storage units, places where electricity can build up to higher levels.
They smooth out variations in power flow.
• Capacitors block the flow of direct current or limit the flow of alternating current.
• Direct current is the type of current generated by batteries - not the kind that comes from wall sockets.
Many battery powered devices also have AC (alternating current, the kind that comes from wall sockets) adapters so they can run on household current as well.
• Alternating current is the type of current available through wall sockets.
Any device that does not run on batteries is called an AC device. Many battery powered devices (DC) have AC adapters so they can run on alternating current as well.
Resistors
• Resistors reduce the flow of electricity. (like friction)
• Resistors give electricity something to do.
Electricity without something to do is a short circuit and a bad thing so you will have to at least some resistance in every circuit.
Resistors usually have two leads with no polarity (no positive and negative side) so the leads are interchangeable.
Transistors
• Transistors are like switches that are switched on and off by electricity instead of by your finger.
Transistors usually have 3 leads, a Base, a Collector and an Emitter.
Transformers
• A transformer is a device made up of coiled wire wrapped around an iron core.
It is used to convert electric power from one voltage level to another. Some transformers increase voltage while others lower it.
The iron core in the transformer acts as a magnetic link between the input coil and the output coil.
Electric current from the input coil creates a magnetic field in the core, which in turn produces a voltage on the output coil.
The iron core concentrates the magnetic field inside the coils and increases the efficiency of the transformer.

Electricity Story
Electricity and Magnetism Demos
Electricity
Shocking
Brainpop
Electricity Charged
Energy
Experiments
Theatre of Electricity
Articles on Electricity
Resources
Zoom School Static
Basics
Pro Teacher Lessons
Interactive
Simple Circuits
Bibliography
Word Document Lessons
Circuits and Schematics
Science Toys
Electrical Safety

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