Opposing torque

Against an opposing torque, the accelerating torque of the motor, which hitherto had varied in proportion to the type of switching, will now diminish disproportionately... 

Motor speed-torque curve NEMA rotor designs Special designs of rotors Effect of starting current on torque Load torque or opposing torque Selection of motors Time of start-up and its effect on motor performance Thermal withstand time... 

When the mill is in operation, the mass of grinding media and feed material forms an irregularly shaped asymmetrical body whose centre of gravity is at a distance a from the vertical centre-line of the mill cross-section. The opposing torque is thus equal to the weight G of the grinding media multiplied by the distance a, i.e. M = g xa. 

The current in the copper ring opposes the main flux in that area of the pole and behaves like an artificial second winding, and develops a rotating field. Although the torque so developed is extremely low, it is enough to rotate such small drives, requiring an extremely low starting torque, of the order of 40-50% of the full load torque. 

Figure 12-20. Fourth- and fifth-stage cylinder assembly of 3,500 psig pressure hydrogen compressor. Opposed single-acting cylinders balance frame-bearing loading and minimize torque fluctuations. (Used by permission Dresser-Rand Company.)...

When immersed in a magnetic field, a nueleus will experience a twisting force, or torque, which tends to line the spin axis of the nucleus up with the field, the same effect that causes two bar magnets to stick to each other in opposed directions. Because the nucleus is spinnirig, however, it will precess like a spinning top or gyroscope. 

The dimensionless group y is the ratio of the applied torque to the maximum gravitational torque. If / > 1 then the applied torque can never be balanced by the gravitational torque and the pendulum will overturn continually. The rotation rate is nonuniform, since gravity helps the applied torque on one side and opposes it on the other (Figure 4.4.2). 

The torque, T, opposing rotation of the propeller (and inducing fluid flow) is given by ... 

Other important parameters are the shear modulus or modulus or rigidity (G), which is the mount s (or other elastomeric components ) ability to resist shear when forces are applied in opposing directions. For instance, there could be engine torque applying a load in a particular direction upon hard acceleration, while simultaneously a road impact force could be applied to the frame in another direction. This quantity is represented by the shear stress (x) over shear strain (e). Finally, the bulk modulus (K) plays a role in these types of components. The bulk modulus describes how a component elastomer will behave under pressure in three dimensions. Volume is considered here and typical units are in gigapascals (GPa). Equation 2.11 describes the bulk modulus mathematically, and Figure 2.7 shows the value graphically. 

Fig. 1.2. The field induced magnetic moment is depicted schematically in this drawing. This effect is most pronounced in aromatic molecules such as fluorobenzene, where comparatively strong electron ring currents may be induced, leading to a field induced, molecular magnetic dipole moment which opposes the exterior field. Trying to align the induced moment, the exterior field will exert a torque ind X H on the molecule and will thus perturb the overall rotation. This perturbation is seen as a splitting in the rotational spectra. Since there will be a torque only in the case that md and H are not aligned, i.e., if Jg is anisotropic, only the anisotropies of the molecular susceptibility tensor can be obtained from the splittings of the rotational lines...

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