ECE106 Lecture Notes - Lecture 62: Resistor, Electric Field, Temperature Coefficient

• School: University of Waterloo
• Department: Electrical and Computer Engineering
• Course: ECE106
• Professor: All

Document Summary

If a is small, we can make uniform current density and electric field assumption e = v/l, and. In general, if e and j were not uniform, S j ds a (7. 18) (7. 19) (7. 20) Resistivity of any material is a function of temperature, i. e. , the second order approximation of resistivity is a linear function of t , (t ) = 0 [1 + t (t t0)] (7. 21) here, 0 is resistivity of the material at the reference temperature (t0); t is the average temperature coefficient of resistivity (typically a constant over a range of temperature). = r0 [1 + t (t t0)] (7. 22) Say in time dt, dq amount of charge is transferred from the + electrode to the electrode through the power consuming device. Potential energy lost by the source in this process must have been consumed by the device (conservation of energy), i. e. , or du = dq vab = (idt) vab du dt.