Ohmic Conductors and Non-Ohmic Conductors

As per the earlier discussion on Ohms Law,

V = Applied Voltage

R = Resistance

I = Current.

For a constant temperature the resistance is a constant therefore the following relationship can be obtained,

V α I

That is that the Voltage applied is directly proportional to the current generated, which directly means that the relationship is linear.

Consider the following graph.

Here the current has a linear relationship with voltage where the current is linearly proportional to the voltage, hence it obeys the ohms law these types of conductors are known as ohmic conductors.

Consider the following relationship,

The current and the Voltage does not have a linear relationship, that indirectly that the resistance changes throughout the course of the change of voltage and current therefore these conductors are called as non ohmic conductors.

Examples for Ohmic and Non Ohmic Conductors..

Cu wires conduct current linearly with the voltage that is if the voltage increase then the current increases therefor it is an ohmic conductor.

Resistors are also ohmic conductors since the too show the same characteristics.

Now consider the IV characteristics of a Diode.

Note that the current and voltage does not show a linear relationship even under forward or reversed biased conditions therefore diodes are considered as non ohmic.

Consider the I-V characteristic of a filament bulb,

Here too the current and the voltage does not have a linear relationship the resistance of the filament changes due to the increase in temperature therefore it does not behave as per the ohms law hence it is considered to be non ohmic.

Some other similar examples for non ohmic conductors are,

· Thermistors

· Crystal Rectifiers

· Vacuum Tubes

· Semiconductors

Ohms Law

Scientific Research that does not have a commercial aim are called blue skies research. The discovery of superconductivity was made about 100 years ago but the applications have been available only in the past decade or so.

These innovations are really expensive if a superconductor in room temperature is not found or achieving new to use very cold temperatures in the atmosphere.

Ohm’s Law

The Ohms law can be defined as, at a constant temperature, the current flowing through a fixed linear resistance is directly proportional to the voltage applied across it and is inversely proportional to its resistance.

This law is named as Ohms law in honor of its founder George Ohms. The unit of measurement of resistance is also called Ohms denoted by Ω.

The relationship expressed can be denoted in the formula as such.

By using the ohms law, it can be said that the current flowing across a resistor of 1Ω with an applied voltage of 1V is 1A.

Today for the purpose of remembering the ohms law triangle is introduced.

It is as follows;

Which gives rise to the equations,

With the use of this Ohms law it can give rise to equations for power, where we will be discussing the Ohms law pie chart as well as Ohms law matrix table as well in the latter discussion on Power.

Get a glimpse of it as follows,

Ohms law pie chart.