 556  457. The amount of energy of any river depends upon two circumstances, its volume and its velocity. Other things being equal, the velocity is dependent upon the inclination of the river-course: the steeper the slope, the greater the velocity. 458. Even if space were available to reduce the bandwidth of this filter it would do no good because the filter delay, which contributes an appreciable part of the circuit delay, would increase and the frequency of oscillation would decrease, so the filter would have little effect on AM gain at the lower frequency. 459. Attention is now turned to the case of active network with the parts considered in sequence again. The definition of two models at the outset is now a major task. No longer do models necessarily bear a one to one correspondence with the physical elements. 460. The motor actuates a hydraulic valve that causes the controlling piston to move in the direction necessary for correction. If the edge of the material pushes the sensing lever to the left, for instance, the piston is made to move to the right until a zero voltage is produced. 461. In fact, it seems to be generally the case that whenever a mechanism is provided for changing the electron-to-ion space-charge ratio, the possibility of attaining an unstable space-charge 571 configuration exists, which in turn would result in current oscillations. 462. We know that the electrical system in an automobile and an airplane uses direct current and so do the telegraph, the telephone, and the train, to say nothing of laboratories requiring direct current for their experimental work. 463. In any discussion of space vehicles, whether they be of the transitory type such as missiles, or whether they be orbiting or stationary satellites, certain limitations are immediately apparent that do not exist with ground-based equipment. 464. The Gattermann reaction and the method explored by Bisagni, Buu-Hoi and Royer were both used for this conversion and found to give comparable yields. The latter being much the more convenient, it is now preferred. 556 |
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