Search results
Results from the WOW.Com Content Network
where the real part of impedance is the resistance R and the imaginary part is the reactance X. Where it is needed to add or subtract impedances, the cartesian form is more convenient; but when quantities are multiplied or divided, the calculation becomes simpler if the polar form is used.
The real part of impedance, [()], is in general frequency dependent and so the Johnson–Nyquist noise is not white noise. The RMS noise voltage over a span of frequencies f 1 {\displaystyle f_{1}} to f 2 {\displaystyle f_{2}} can be found by taking the square root of integration of the power spectral density:
The input impedance of an infinite line is equal to the characteristic impedance since the transmitted wave is never reflected back from the end. Equivalently: The characteristic impedance of a line is that impedance which, when terminating an arbitrary length of line at its output, produces an input impedance of equal value. This is so because ...
Impedance is the reciprocal of mobility. If the potential and flow quantities are measured at the same point then impedance is referred as driving point impedance; otherwise, transfer impedance. Resistance - the real part of an impedance. Reactance - the imaginary part of an impedance.
Parts of this article or section rely on the reader's knowledge of the complex impedance representation of capacitors and inductors and on knowledge of the frequency domain representation of signals. The impedance, Z, is composed of real and imaginary parts, = +, where R is the resistance (ohms); and; X is the reactance (ohms).
In electrical engineering, susceptance (B) is the imaginary part of admittance (Y = G + jB), where the real part is conductance (G). The reciprocal of admittance is impedance (Z = R + jX), where the imaginary part is reactance (X) and the real part is resistance (R). In SI units, susceptance is measured in siemens (S).
Electrical impedance, like electrical resistance, is measured in ohms. In general, impedance (symbol: Z) has a complex value; this means that loads generally have a resistance component (symbol: R) which forms the real part and a reactance component (symbol: X) which forms the imaginary part.
The impedance analogy is a method of representing a mechanical system by an analogous ... Electrical resistance represents the real part of electrical impedance.