There is a resistanceThe opposition in an electrical component to the movement of electrical charge through it. Resistance is measured in ohms. to the flow of an electric currentMoving electric charges, eg electrons moving through a metal wire. through most conductorA material which allows charge to move easily through it..
The resistance in a wire increases as:
the length of the wire increases
the thickness of the wire decreases
An electric current flows when electronSubatomic particle, with a negative charge and a negligible mass relative to protons and neutrons. move through a conductor, such as a metal wire. The moving electrons can collide with the ionElectrically charged particle, formed when an atom or molecule gains or loses electrons. in the metal. This makes it more difficult for the current to flow, and causes resistance.
Resistance is best summarised as a measure of a component’s opposition to currentMoving electric charges, eg electrons moving through a metal wire..
