Compare the effects of temperature increase on resistivity of thermistor andcopper wire

The resistivity of a material is a measure of how strongly it opposes the flow of electric current. The effect of temperature on resistivity varies depending on the type of material.

1. Thermistor: A thermistor is a type of resistor whose resistance is dependent on temperature. Thermistors are made from semiconductor materials. For a thermistor, as the temperature increases, the resistivity decreases. This is because the increase in temperature provides more energy to the semiconductor electrons, which allows them to jump into the conduction band and increase the current flow. Therefore, thermistors are often used in temperature sensing devices.

2. Copper Wire: Copper is a metal with a positive temperature coefficient of resistance. This means that as the temperature increases, the resistivity of the copper wire also increases. The reason for this is that as the temperature increases, the amplitude of vibration of the copper atoms increases. This causes more frequent collisions between the free electrons and the vibrating atoms, which increases the resistance to the flow of current.

In conclusion, an increase in temperature decreases the resistivity of a thermistor and increases the resistivity of a copper wire.