How does temperature affect resistance in conductors?
1 Answer
Temperature has a significant impact on the resistance of conductors. The relationship between temperature and resistance is generally described by the temperature coefficient of resistance (TCR). Here's how it works:
Increased Temperature, Increased Resistance: In most materials, including conductors, as the temperature increases, the resistance of the material also increases. This means that the material becomes less conductive as it gets hotter.
Atomic Vibration: The behavior of electrons and atoms in a material is influenced by temperature. When the temperature rises, the atoms in the material vibrate more vigorously, and this vibration can disrupt the smooth flow of electrons. This disruption leads to an increase in resistance because the electrons encounter more obstacles while moving through the material.
Collision Frequency: In a conductor, electrons move through the lattice of atoms. At lower temperatures, the atoms vibrate less, allowing electrons to move more freely with fewer collisions. As temperature increases, the collision frequency between electrons and vibrating atoms rises, causing the electrons to slow down and creating more resistance to their movement.
TCR Value: The temperature coefficient of resistance (TCR) is a parameter that quantifies how much a material's resistance changes with temperature. It is defined as the fractional change in resistance per degree Celsius (or Kelvin) change in temperature. Different materials have different TCR values, and these values can be positive or negative.
If a material has a positive TCR, its resistance increases as temperature rises.
If a material has a negative TCR, its resistance decreases as temperature rises. Some materials, like semiconductors, exhibit this behavior under specific conditions.
Superconductors: It's worth mentioning that there are materials known as superconductors that exhibit zero electrical resistance at very low temperatures, typically close to absolute zero (-273.15°C or 0 Kelvin). In these materials, the vibrations that hinder electron movement are almost entirely eliminated, allowing for perfect conductivity.
In summary, the increase in temperature causes increased atomic vibrations and higher collision frequencies between electrons and atoms, leading to an increase in resistance in most conductive materials. This relationship is quantified by the temperature coefficient of resistance, which varies from material to material.
Increased Temperature, Increased Resistance: In most materials, including conductors, as the temperature increases, the resistance of the material also increases. This means that the material becomes less conductive as it gets hotter.
Atomic Vibration: The behavior of electrons and atoms in a material is influenced by temperature. When the temperature rises, the atoms in the material vibrate more vigorously, and this vibration can disrupt the smooth flow of electrons. This disruption leads to an increase in resistance because the electrons encounter more obstacles while moving through the material.
Collision Frequency: In a conductor, electrons move through the lattice of atoms. At lower temperatures, the atoms vibrate less, allowing electrons to move more freely with fewer collisions. As temperature increases, the collision frequency between electrons and vibrating atoms rises, causing the electrons to slow down and creating more resistance to their movement.
TCR Value: The temperature coefficient of resistance (TCR) is a parameter that quantifies how much a material's resistance changes with temperature. It is defined as the fractional change in resistance per degree Celsius (or Kelvin) change in temperature. Different materials have different TCR values, and these values can be positive or negative.
If a material has a positive TCR, its resistance increases as temperature rises.
If a material has a negative TCR, its resistance decreases as temperature rises. Some materials, like semiconductors, exhibit this behavior under specific conditions.
Superconductors: It's worth mentioning that there are materials known as superconductors that exhibit zero electrical resistance at very low temperatures, typically close to absolute zero (-273.15°C or 0 Kelvin). In these materials, the vibrations that hinder electron movement are almost entirely eliminated, allowing for perfect conductivity.
In summary, the increase in temperature causes increased atomic vibrations and higher collision frequencies between electrons and atoms, leading to an increase in resistance in most conductive materials. This relationship is quantified by the temperature coefficient of resistance, which varies from material to material.