The resistance of an alloy increases with temperature.


When an electric current flows through a material, it encounters resistance, which is the opposition to the flow of electric charge. The resistance of a material depends on various factors, including temperature.


The resistance of most materials, including metals and alloys, increases with an increase in temperature. This phenomenon is referred to as the positive temperature coefficient of resistance.

Factors contributing to the increase in resistance with temperature:


As the temperature of a material increases, the atoms or ions in the material gain thermal energy and start vibrating more vigorously. This increased atomic vibration leads to more frequent collisions between the moving electrons and the vibrating atoms. These collisions impede the flow of electrons, increasing the resistance.


The increased atomic vibrations also result in more collisions between the electrons and the atoms. These collisions scatter the electrons, making it more difficult for them to move through the material. Consequently, the resistance of the material increases.


At higher temperatures, the electron mobility, which is the ability of electrons to move freely in a material, decreases. This decrease in electron mobility further contributes to the increase in resistance.


There are a few materials, such as certain semiconductors and superconductors, that exhibit a negative temperature coefficient of resistance. In these materials, the resistance decreases with an increase in temperature.


In the case of alloys, which are typically metallic substances composed of two or more elements, the resistance increases with temperature due to the increased atomic vibrations, electron-atom collisions, and reduced electron mobility. This phenomenon is important to consider in various applications, such as electrical circuits and devices, where temperature changes can affect the overall performance and efficiency.

When the temperature increases, the free electrons start to move more randomly.
This causes more collisions within the alloy, resulting difficult in moving electrons and cause more resistance.

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