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The Level of Resistivity

The current flowing in a conductor always encounter the resistance of the conductor itself. The major obstacle depending on the type of conducting material used. Major obstacles to the cross-sectional area of each meter 1mm 2 at temperatures of 200 ° C is called the resistivity or resistivity.

Conductor Resistance
As you already know, that when the movement of free electrons in a material, without direction or speed, and influenced by the style so that it moves in a coordinated manner by means of a conductive material, the movement of electrons is called an electric evenly or electric current. Just as water flowing through a pipe, the electrons can move through the empty space between the atoms of the conductor.

Conductor may be seen as a solid body, but the materials are composed of atoms are mostly empty space. The analogy of water flow so fit so that the movement of electrons through a conductor is often referred to as “flow”. For the purposes of the distribution of electric current effectively and efficiently, it is necessary that the conductor material has a high conductivity or have a low resistance value.

Here are some examples of conducting material commonly used for the delivery of electrical current: silver, copper, gold, aluminum, mercury, and graphite. A material having a low conductivity, among others, glass, rubber, oil, asphalt, fiber glass, porcelain, ceramic, quartz, cotton, paper, wood, plastic, air, diamond, and pure water. Conductors or electrical conductors are materials that have electrical large electrical conductivity so that electric current is flowing in it.

Which includes a group of conductors are all metals and alloys. Types of metal having large electrical conductivity and widely used is copper, and aluminum. Electric current is meant here can be strong currents (electric current) and can be either a weak current (signal). Conductor resistance value is measured in ohms, typically ranging from: 0,000 001 or 1 × 10 -6 ohm, 0.00001 or 1 × 10 -5 ohm, 0.0001 or 1 × 10 -4 ohm to 0,001 or 1 × 10 -3 ohm.

The resistance value of the conductor material must be very small, so that the voltage loss caused to be very small. Physically, the resistance value of a conductor material, depending on:
– The length of conductors used in (m)
– Cross-sectional area of ​​conductors used in (m2)
– The type of conductor used

Conductor Material Type
The materials used for the conductor must meet the following requirements:
1. quite good conductivity.
2. The strength of the mechanical (tensile strength) is high enough.
3. The length expansion coefficient is small.
4. The elastic modulus (modulus of elasticity) is quite large.

The materials used as conductors, among others:
1. ordinary metals, such as copper, aluminum, iron, and so on.
2. Metal mixture (alloy), which is a metal of copper or aluminum are given a certain amount of other types of metal, which is useful to increase the mechanical strength.
3. Metal alloy (composite), ie two or more metals, combined with the compression method, smelting (smelting) or welding (welding).