PHYS 1062 Lecture Notes - Lecture 8: Magnetic Monopole, Electric Field, Root Mean Square
Document Summary
The instructor planned to do too many topics last friday, oct. 19: (a) to complete chap. 30, and (b) to discuss several topics in chap. But we only discussed one topic in chap. The following topics were already written on the outline for oct. 19. Average power in ac circuits (section 31-10) Root-mean-square current (i rms) and voltage (vrms): transformer (section 31-11, power transmission. Transformers play an important role in the transmission of power between electrical generating plants and the communities they serve. Whenever electricity is transmitted, there is always some loss of power in the transmission lines themselves due to resistive heating (p=i2r). Since the resistance of the wires is proportional to their length, the longer the wires the greater is the power loss. Power companies reduce this loss by using transformers that step up the voltage to very high levels, while reducing the current to very small levels.
