# Ohmic Conductors vs. Non-Ohmic Conductors: What's the Difference?

Edited by Aimie Carlson || By Janet White || Published on February 23, 2024
Ohmic conductors have a linear relationship between voltage and current, obeying Ohm's Law; non-ohmic conductors show a nonlinear relationship, deviating from Ohm's Law.

## Key Differences

Ohmic conductors exhibit a direct proportionality between voltage and current, meaning as voltage increases, current increases linearly. This relationship adheres to Ohm's Law. Non-ohmic conductors, however, do not maintain this linear relationship. Instead, their current-voltage relationship is nonlinear, showing variations due to factors like temperature or light exposure.
In a current-voltage graph, ohmic conductors display a straight line, indicating constant resistance. Non-ohmic conductors, on the other hand, show a curved or irregular line on such graphs, reflecting their changing resistance under different electrical conditions.
Materials like copper and aluminum are examples of ohmic conductors, commonly used in electrical circuits for their predictable behavior. Non-ohmic conductors include materials like semiconductors and diodes, where the current-voltage relationship can change dramatically.
Ohmic conductors are widely used in standard electrical components like resistors and wires, where consistent and reliable conductivity is required. Non-ohmic conductors find their applications in electronic devices like transistors, solar cells, and light-emitting diodes (LEDs), where variable resistance is beneficial.
In ohmic conductors, resistance remains relatively unaffected by external factors at constant temperature. Non-ohmic conductors can exhibit significant changes in resistance due to factors like temperature changes, light, and magnetic fields.

## Comparison Chart

### Voltage-Current Relationship

Linear relationship, obeys Ohm's Law
Nonlinear relationship, deviates from Ohm's Law

### Graphical Representation

Straight line in a current-voltage graph
Curved or irregular line in a current-voltage graph

### Types of Materials

Metals like copper, aluminum
Semiconductors, diodes

### Applications

Standard electrical components
Electronic devices like transistors, LEDs

### Effect of External Factors

Minimal effect from external factors
Resistance changes with temperature, light

## Ohmic Conductors and Non-Ohmic Conductors Definitions

#### Ohmic Conductors

Have a predictable response to voltage changes.
Ohmic conductors are preferred in circuits for their predictable behavior.

#### Non-Ohmic Conductors

Include materials like semiconductors and diodes.
Silicon, a non-ohmic conductor, is widely used in semiconductor technology.

#### Ohmic Conductors

Materials that obey Ohm's Law with a constant resistance.
Copper wires, as ohmic conductors, are used extensively in home wiring.

#### Non-Ohmic Conductors

Deviate from Ohm's Law with a nonlinear current-voltage relationship.
The diode, a non-ohmic conductor, showed a nonlinear response in the circuit.

#### Ohmic Conductors

Show a linear voltage-current relationship.
In the experiment, the ohmic conductor displayed a linear graph.

#### Non-Ohmic Conductors

Used in electronic components for variable conductivity.
Transistors, made from non-ohmic conductors, are crucial in modern electronics.

#### Ohmic Conductors

Unaffected by external factors at constant temperature.
The resistance of the ohmic conductor remained stable despite changes in lighting.

#### Non-Ohmic Conductors

Exhibit changing resistance under various conditions.
In our tests, the non-ohmic conductor's resistance changed with temperature.

#### Ohmic Conductors

Often made of standard conducting materials like metals.
Aluminum, an ohmic conductor, is commonly used in electrical cables.

#### Non-Ohmic Conductors

Sensitive to external factors like light and temperature.
This non-ohmic conductor's resistance decreased under bright light.

## FAQs

#### Can the resistance of a non-ohmic conductor be constant?

No, non-ohmic conductors typically have variable resistance under different electrical conditions.

#### What is an ohmic conductor?

An ohmic conductor follows Ohm's Law, showing a linear relationship between current and voltage.

#### What is a non-ohmic conductor?

A non-ohmic conductor does not follow Ohm's Law, exhibiting a nonlinear current-voltage relationship.

#### Is copper wire an ohmic conductor?

Yes, copper wire is a typical example of an ohmic conductor.

#### What causes non-ohmic behavior?

Non-ohmic behavior is often caused by factors like temperature changes, material properties, or light exposure.

#### Are all metals ohmic conductors?

Most metals are ohmic conductors, but there are exceptions depending on the metal's structure and conditions.

#### Are ohmic conductors temperature dependent?

While ohmic conductors can be affected by temperature, their resistance remains largely constant at a fixed temperature.

#### Are resistors always ohmic conductors?

Most resistors are designed to be ohmic conductors, but some specialized types may exhibit non-ohmic properties.

#### How do semiconductors behave in terms of ohmic and non-ohmic conduction?

Semiconductors can behave as non-ohmic conductors, especially under varying temperature and electrical conditions.

#### Can a material switch between ohmic and non-ohmic conduction?

Yes, certain materials can exhibit both behaviors depending on conditions like temperature and electrical field strength.

#### What are practical applications of non-ohmic conductors?

Non-ohmic conductors are used in electronics, such as in diodes, transistors, and photocells.

#### How do LEDs exhibit non-ohmic behavior?

LEDs, as non-ohmic conductors, have a threshold voltage below which they do not conduct significantly.

#### Are gold and silver ohmic conductors?

Gold and silver are typically ohmic conductors under normal conditions.

#### Can non-ohmic conductors be used for resistors?

Non-ohmic conductors are generally not used for standard resistors due to their variable resistance.

#### Why are ohmic conductors preferred in basic electrical circuits?

Ohmic conductors are preferred for their predictable and consistent resistance, which is crucial for stable circuit operation.

#### Can environmental conditions affect ohmic behavior?

Extreme environmental conditions can affect the ohmic behavior of a conductor, although under normal conditions, ohmic conductors maintain their linearity.

#### Do non-ohmic conductors have a linear IV graph?

No, non-ohmic conductors typically have a curved or nonlinear current-voltage (IV) graph.

#### Do all ohmic conductors have the same resistance?

No, different ohmic conductors have varying levels of resistance based on their material properties.

#### What defines the threshold voltage in non-ohmic conductors?

Threshold voltage in non-ohmic conductors is defined by the material's properties and the nature of the conduction mechanism.

#### How does a filament lamp exhibit non-ohmic behavior?

A filament lamp shows non-ohmic behavior as its resistance increases with temperature, deviating from Ohm's Law.