Conductors: The materials that allow electric current to pass through them.
Examples: Iron nail, copper wire, brass key, aluminium rod, pencil lead (graphite), mercury..etc.
*All metals are good conductors of electricity.
*Human body is good conductor of electricity.
*All liquids are bad conductors of electricity except mercury which is a liquid metal.
*Pure water is a bad conductor of electricity.
Insulators (or) Non-conductors:
The materials which does not allow electric current to pass through them.
Ex: Paper, wood, plastic, cloth, eraser (rubber), pure water....etc.
Conductors of electricity are coated with insulators to prevent leakage of electricity.,
Semiconductors:
The materials which allows electricity partially to pass through them is called semiconductors
Ex: Silicon , germanium.. etc
Symbols used in Electrical circuits:
Device Symbol
1.An electric cell
2.An electric bulb
3.A plug key (as a switch)
4.A tap key (as a switch)
5.A voltmeter
6.An Ammeter
7.A resistance
8.A Rheostat
9.A fuse