<^< Examples: Resistance and Temperature | Course Index | Negative Temperature Coefficient >^>
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Where the resistance of the material increases with temperature, it is said to exhibit a positive temperature coefficient (PTC). Metals like copper have a positive temperature coefficient.
The video clip shows how the resistance of an PTC resistor increases as the surrounding temperature increases. We are using a candle as a simple heat source. The meter reading moves towards the left hand end of the scale when the thermistor gets hot. Note that, on simple analogue multimeters, zero resistance coincides with full-scale deflection. In other words, if the pointer moves to the left the resistance is increasing whereas if it moves to the right the resistance is decreasing.
<^< Examples: Resistance and Temperature | Course index | Negative Temperature Coefficient >^>
