Characteristics of Ohmic and non-Ohmic Conductors Essay Example
Characteristics of Ohmic and non-Ohmic Conductors Essay Example

Characteristics of Ohmic and non-Ohmic Conductors Essay Example

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  • Pages: 2 (426 words)
  • Published: July 4, 2017
  • Type: Essay
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Some atoms contain loosely attached electrons. These electrons can be made to move easily from one atom to another. When these electrons move freely along a path, a current of electricity is created. Electrons can only flow freely in materials that conduct electricity. A Conductor of electricity is a substance that allows electricity to flow through it. Substances that do not conduct electricity are knows as Insulators. All metals are good conductors because inside them they have a large number of free electrons that can move easily from atom to atom.

Insulators do not have free electrons inside them. Current is the flow of free electrons through a conductor in one particular direction. Current is also calculated by the amount of charges transferred per second. For current to flow, we need a cell to exert a force and provide energy. The Current

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flowing in a circuit depends on the cells ability to give energy. Voltage is the energy given by the cell per charge. Another factor that affects current is Resistance. As electrons pass through the conductor they encounter collisions with atoms or ions.

Electrons lose their energy and the atoms gain. The atoms vibrate with more amplitude for a while, till it emits the extra energy as heat. The 1862, George Ohm discovered that the current flowing through a metal wire is proportional to the potential difference across it (provided the temperature remains constant). However this law does not apply to all conductors, due to resistance of a wire. Thus, conductors can be divided into Ohmic and Non-Ohmic conductors. In non-ohmic conductors current is not always proportional to voltage.

Sometimes, when voltage increases current decreases. Also w

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can say that Semi conductors are non-ohmic conductors, because as a current increases in a semi conductor, it gets hotter and so the energy is used to liberate more free electrons. As the number of free electrons increase, resistance decreases. Ohmic Conductors Metallic Conductors A metal contains a large number of almost 'free' electrons. This property makes metals extremely good conductors of electricity.

But as the temperature of the metal increases the ions in the metal vibrate vigorously, colliding with the free flowing electrons, obstructing the flow of electricity, thus as temperature increases, resistance increases as well. Metallic conductors are Ohmic Conductors. In ohmic conductors, Current is always proportional to the voltage. As voltage increases, current increases too. This is because as the voltage increases, more electrons have the energy to flow through the conductor, causing the current to increase simultaneously, (provided the temperature of the conductor remains constant).

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