Frequency characteristics(Xi, xc,x,z, y, o vs o Z=R+A=R+(L+Xc)=R+ilo I

A current i at Li produces an open circuit voltage u,at L2s dyal

An ideal transformer is a useful approximation of a very tightly coupled transformer in which the coefficient of coupling is almost unity and both the primary and secondary inductive reactance are extremely large in comparison with the terminating impedance

Three-phase sources have three Q terminals called the line terminals(a, b,c). + Neutral connection--n an b+V n bn Balanced three-phase sources may

If a positive current is flowing into the(+) end of the current coil while the(+) terminal of the voltage coil is positive with respect to the unmarked end, an upscale reading is obtained

parameters equivalents admittance parameters. They parameter equivalents matrix form:

are parameters The matrix from of parameter equations:

the open-circuit reverse voltage gainthe open-circuit transfer admittancethe short-circuit transfer impedancethe short-circuit reverse current gain

current of one port into the voltage of the otherport and vice verse. U1 =-ais \2 =ai..gyration constant

Any periodic waveform f(t)f(t) can be expressed by a Fourier series provided that (1) If it is discontinuous, there are only a finite number of discontinuous in the period T (2)It has a finite average value over the period T (3)It has a finite number of positive and negative maximums in the period T