Question

As the temperature increases, the electrical resistance:

• A. Increases for both conductors and semiconductors
• B. Decreases for both conductors and semiconductors
• C. Increases for conductors but decreases for semiconductors
• D. Decreases for conductors but increases for semiconductors

Answer 1

The Correct Option is C

As temperature increases, the behavior of electrical resistance varies between conductors and semiconductors due to their different properties:

• Conductors: In conductors, such as metals, resistance typically increases with temperature. This is because higher temperatures cause atoms to vibrate more intensely. These vibrations cause increased collisions with the conduction electrons, which hampers their flow, leading to increased resistance. The relationship is often linear and can be represented by the equation: R = R₀(1 + αT), where R is the resistance at temperature T, R₀ is the resistance at a reference temperature, and α is the temperature coefficient of resistance.
• Semiconductors: In semiconductors, such as silicon, resistance decreases with temperature increase. This is due to the increased number of charge carriers available for conduction. At higher temperatures, more electrons in a semiconductor gain the energy needed to jump into the conduction band, reducing the material's resistance. This phenomenon leads to an increase in conductivity as temperature rises.

Therefore, the correct answer is:

Increases for conductors but decreases for semiconductors