Electrical Circuits

Getting the Idea Whenever you turn on a lamp or watch TV, you are using electrical energy. This energy is in the form of a flow of charged particles called an electric current. Electric current moves in predictable ways. Whenever you turn on a lamp or watch TV, you are using electrical energy. This energy is in the form of a flow of charged particles called an electric current. Electric current moves in predictable ways. An electrical circuit is the path that an electric current takes. An electrical circuit is the path that an electric current takes.

Electrical Circuits Electrical circuits allow electrical energy to do work. Electrical energy can do work only in a closed circuit. Electrical circuits allow electrical energy to do work. Electrical energy can do work only in a closed circuit. A loop through which electric current travels A loop through which electric current travels Does not have any breaks in it Does not have any breaks in it An open circuit has at least one break in the loop that interrupts the flow of the current. An open circuit has at least one break in the loop that interrupts the flow of the current.

A closed circuit and an open circuit have three main parts: A closed circuit and an open circuit have three main parts: 1. An electrical source 1. An electrical source 2. an output device 2. an output device 3. and a connection between the source and output device 3. and a connection between the source and output device

Electrical sources can be anything that supplies electric current Electrical sources can be anything that supplies electric current Examples: sockets, batteries, etc. Examples: sockets, batteries, etc. An output device is anything that uses electric current An output device is anything that uses electric current Examples: light bulb, refrigerator, etc Examples: light bulb, refrigerator, etc

The connection between a source and an output device must be a conductor. The connection between a source and an output device must be a conductor. Electrical Conductors allow electric currents to easily pass from the source to the output device without any resistance Electrical Conductors allow electric currents to easily pass from the source to the output device without any resistance Good conductors of heat are also good conductors of electric current Good conductors of heat are also good conductors of electric current Example: metal wire, especially copper Example: metal wire, especially copper

Electrical Insulators are materials that resist the flow of electricity. Electrical Insulators are materials that resist the flow of electricity. Electricity does NOT pass easily through them. Electricity does NOT pass easily through them. Examples: electrical tape, plastic, or wood Examples: electrical tape, plastic, or wood

Series Circuits When two or more output devices are connected in a circuit in a single loop, it is called a series circuit. In a series circuit, electric current flows into one output device and then flows into the next. When two or more output devices are connected in a circuit in a single loop, it is called a series circuit. In a series circuit, electric current flows into one output device and then flows into the next. If you remove one of the output devices, the other will not work If you remove one of the output devices, the other will not work

Review The Blobz Guide to Electrical Circuits: The Blobz Guide to Electrical Circuits: productions.info/hyper/Hypermedia_2003/Thelwell/Sit e/ productions.info/hyper/Hypermedia_2003/Thelwell/Sit e/ productions.info/hyper/Hypermedia_2003/Thelwell/Sit e/ productions.info/hyper/Hypermedia_2003/Thelwell/Sit e/ Who Can Resist?: Who Can Resist?: Engineering Interactive: Electricity, simple circuit Engineering Interactive: Electricity, simple circuit pies/flash/concepts/simplecircuits.htm pies/flash/concepts/simplecircuits.htm pies/flash/concepts/simplecircuits.htm pies/flash/concepts/simplecircuits.htm