Electrical root-mean-square

Roman geomembrane See geomembrane, roofing See bitumen plastic house, root-mean-square See deviation, root-mean-square, root-mean-square, electrical See electrical root-mean-square voltage. 

An electrical measuring instrument contains electrical circuits incorporating capacitance, inductance, and resistance. In the absence of resistance, a circuit tends to oscillate with a definite frequency /when disturbed. For optimum performance an amount of resistance is incorporated that is barely sufficient to damp the oscillations resulting from transient inputs the circuit is then said to be critically damped. For a critically damped circuit it can be shown that the root-mean-square (rms) fluctuations in voltage V and in current /are given by... 

There are two types of noise relevant to chromatographic-determinations. Detector, or electrical, noise is the random fluctuation of the baseline signal in the presence of mobile-phase flow. Noise values can be reported as either peak-to-peak values, or as a root-mean-square (rms) value. The rms value can be estimated easily as A the peak-to-peak value. This estimation follows from statistical considerations noise is a randomly occurring phenomenon, and as such the values should follow Gaussian statistics. Ninety-nine percent of the values should then fall within the mean value 2.5 standard deviations. It has been recommended that the baseline region measured be sufficiently wide as to encompass at least 20 base widths of the analyte peak (23). The measurement of noise in chromatographic systems has been addressed in detail (23). 

A classification scheme for molecular polarity can be based on the electric potential surrounding the molecule. Traditionally, schemes for ranking molecular polarity are based on electronegativity differences, on molecular dipole moments, or on solubility. The root-mean-square (rms) value of the molecular electric potential can be used for this purpose. Table 1 shows a ranking of 24 small molecules according to their rms electric potential. Note that all of the amides are extremely polar by this criterion, more polar than formaldehyde or water. Hydrogen fluoride is less polar than acetone, acetaldehyde, water, or the amides. At the low end of the polarity scale, the amines are surprisingly nonpolar. As expected acetylene is more polar than ethylene, which is more polar than methane. 

In order to safeguard against electric shock at the far end of the cable, where the AC root mean square voltage may exceed 50 V, the earth loop impedance must be limited to a particular value. This value is such that the fault current should only be passed by the protective device at the supply for a specific period of time, i.e. to satisfy the /-squared- criterion given in sub-section 13.1.1. The correlation of loop impedance, current and time varies with the type of protective device, e.g. fuse. 

The variation of the data from the point charge theory can be accounted for on the assumption that both the charge and magnetic moment of the proton are spread out over a finite distance. On the assumption that the magnetic moment and electric charge have the same distribution, they find that a root mean square ra us of about 7X10" cm fits the data they have obtained at several energies up to 236 Mev. 

Most regulations include a limit on the total harmonic distortion voltage. The purpose of these limits is to safeguard the performance of electrical supply systems. Human safety issues are discussed in Section 8.5.1.2. Since measured AC voltages are root-mean-square values, the total harmonic voltage is the square root of the sum of the squares of the individual harmonics ... 

Dielectric strength (electric strength) n. A measure of the voltage required to puncture an insulating material, expressed in volts per mil of thickness (SI V/rrmi). The voltage is the root-mean-square voltage difference between the two electrodes in contact with opposite surfaces of the specimen at which electrical breakdown occurs under prescribed test conditions. Ku CC, Liepins R (1987) Electrical properties of polymers. Hanser Publishers, New York. Weast RC (ed) (1971) Handbook of chemistry and physics, 52nd edn. The Chemical Rubber Co., Boca Raton, FL. 

PEDOTiPSS planarizes the ITO surface by smoothing surface imperfections and reducing the root-mean-square roughness, e.g. from 10 nm for bare ITO to 3 nm for a 50 nm layer of PEDOT PSS on ITO [152]. Therefore, a PEDOT PSS buffer layer will typically increase the yield of functional devices as the probability of electrical shortages within the active layer is reduced [139, 153],... 

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