Nate Electrical Practice Exam

When the temperature of a negative temperature coefficient material increases, its resistance will:

1. Remain the same

2. Increase

3. Decrease

4. Change by the square of the applied voltage

The correct answer is: Decrease

In a negative temperature coefficient (NTC) material, the fundamental property is that as temperature rises, the resistance of the material decreases. This behavior is contrary to what is observed in most conductive materials, which typically have a positive temperature coefficient (PTC) where resistance increases with temperature. In NTC materials, when the temperature is increased, more charge carriers, such as electrons, gain enough energy to move freely and contribute to conductivity. This increase in charge carrier mobility results in a reduction in resistance. Thus, understanding the nature of NTC materials is crucial: they are often used in applications where temperature sensing or compensation is needed. Their ability to decrease resistance with an increase in temperature allows them to be effective for thermal management in various electronic circuits and devices.