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Answered 2011-09-13 12:13:00

Positive Temperature coefficient indicates that the resistance of material INCREASES with rise in the temperature.

Resistance Temperature COefficient(RTC) is defined as increase in resistance per unit original resistance per unit rise in temperature.

Temperature Coefficient of Resistance=R2-R1/(R1*(T2-T1))


R2:Resistance at temperature T2

R1:Resistance at temperature T1

SO from formula it is clear that if resistance increases with temperature(T2-T1>0 and R2>R1) then Difference R2-R1 will be positive hence RTC will have positive value. But if with increase in temperature(T2-T1>0) resistance decreases(R2<R1) then difference R2-r1 will be negative hence RTC will be negative.

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Negative temperature coefficient of resistance?

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Positive temperature coefficient is if temperature increased then resistance also increased but in negative temperature coefficient if temperature increasing then resistance must decreased.

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The temperature coefficient of resistance is a number used to predict how the resistance of a material changes with changes in temperature. Typically the units are either resistance per temperature or 1/temperature depending on which equation is used for the calculations. For example, in copper the temperature coefficient of resistance is about 0.0039 per change in degrees Celsius. A positive temperature coefficient of resistance means that the resistance of the material will increase as temperature increases. As per the equation or say unit of resistance temperature coefficient, its definition can be given as below: " Rise in temperature per unit initial resistance, when temperature is raised by one degree Celsius is called the resistance temperature coefficient."

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How the resistance of conducting material vary with temperature?

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How the resistance of a material varies with temperature?

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Mathematical relation between resistance and temperature?

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Which semiconductor have positive temperature coefficient?

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