Temperature coefficient of resistance, (alpha), is defined as the amount of change of the resistance of a material for a given change in temperature. A positive value of indicates that R increases with temperature; a negative value of indicates R decreases; and zero indicates that R is constant. Typical values are listed in Table 2.

For a given material, may vary with temperature; therefore, charts are often used to describe how resistance of a material varies with temperature.

An increase in resistance can be approximated from equation (2-2).

where