In a temperature vs. resistance graph, the slope represents the temperature coefficient of resistance (TCR) or temperature sensitivity of the material. The TCR indicates how the resistance of a material changes with temperature.
Different materials have different TCR values, which can be positive or negative. A positive TCR means that the resistance of the material increases as the temperature rises, while a negative TCR indicates that the resistance decreases with increasing temperature.
The slope of the graph gives you the rate of change of resistance with temperature. Mathematically, the slope is calculated as the change in resistance divided by the change in temperature. Therefore, a steeper slope indicates a higher TCR and a more significant change in resistance for a given change in temperature.
By measuring the slope of the temperature vs. resistance graph, you can determine the TCR of a material and understand how its resistance will vary in response to temperature changes. This information is crucial in various applications, such as designing temperature sensors, thermistors, and other electronic devices that rely on temperature-dependent resistance.