The movement of electrons through an electrical cable is both slow and disorderly, the electrons often collide, increasing the temperature of the cable itself.
The energy that produces as heat is called th Joule Effect: E = I2 x R x t
- Light.
There are various ways that electricity can be used to produce light :
· Incandescent bulbs: when an electric current passes through the metallic filament of a light bulb, it produces light. This is called incandescence.
· Fluorescent tubes: the electric current passes through the filament, electrons are emitted into the inert gas, these react with the mercury, creating invisible, ultraviolet light.
· Light-emitting diodes (LED): a LED has layers of semiconductor materials. When electricity is applied to the LED, the electrons and holes cross over into the active layer, where they combine produce particles of light.
- Electromagnetic effects.
The scientist Michael Faraday noticed that electricity could be generated by using a magnet and an electrical conductor. This principle allows os to build dynamos and alternators.
- Sound.
We use bells and buzzers to transform electric current into sound.
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