Its physical properties, permeability by water, extensibility and elasticity, receive their interpretation in the needs of the latter.
For example, the physicist determines the density, elasticity, hardness, electrical and thermal conductivity, thermal expansion, &c.; the chemist, on the other hand, investigates changes in composition, such as may be effected by an electric current, by heat, or when two or more substances are mixed.
For the subjects of this general heading see the articles Mechanics; Dynamics, Analytical; Gyroscope; Harmonic Analysis; Wave; HYDROMechanics; Elasticity; Motion, Laws Of; Energy; Energetics; Astronomy (Celestial Mechanics); Tide.
The development of the rubber industry has now reached a stage at which more exact methods of determining the chemical composition and physical properties (strength and elasticity) of rubber are required.
When caoutchouc is heated slightly above the temperature of boiling water it becomes softer and loses much of its elasticity, which, however, it recoveres on cooling.
- The micas are characterized by a very easy cleavage in a single direction and by the high degree of flexibility, elasticity and toughness of the extremely thin cleavage flakes.
Miscellaneous Effects of Magnetization: Electric Conductivity - Hall Effect - Electro-Thermal Relations - Thermoelectric Quality - Elasticity - Chemical and Voltaic Effects.
The dimensions of a piece of iron, for example, its elasticity, its thermo-electric power and its electric conductivity are all changed under the influence of magnetism.
An experiment by Ewing showed that by the operation of stretching an annealed iron wire beyond the limits of elasticity the permeability under a magnetizing force of about 3 units was reduced by as much as 75%.
The width of the gap may be diminished until it is no greater than the distance between two neighbouring molecules, when it will cease to be distinguishable, but, assuming the molecular theory of magnetism to be true, the above statement will still hold good for the intermolecular gap. The same pressure P will be exerted across any imaginary section of a magnetized rod, the stress being sustained by the intermolecular springs, whatever their physical nature may be, to which the elasticity of the metal is due.
Changes of elasticity are in all cases dependent, not only upon the field, but also upon the tension applied; and, owing to hysteresis, the results are not in general the same when the magnetization follows as when it precedes the application of stress; the latter is held to be the right order.
This condition manifests itself, for example, in mine pillars which are subjected to a weight beyond the limit of elasticity of the mineral of which they are composed.
But their most characteristic, though not perhaps their most general, property is that they combine in themselves the apparently incompatible properties of elasticity and rigidity on the one hand and plasticity on the other.
Per metre, which, for practical purposes, Wertheim takes as giving the limit of elasticity; column 4 gives the breaking strain.
Without elasticity of dimensions, it is also without known counterpart.
It may be noted that the elasticity E is only constant for small volume changes or for small values of dy/dx.
The energy of this fork with a given amplitude of vibration could be calculated from its dimensions and elasticity, and the amplitude was observed by measuring with a microscope the line into which the image of a starch grain on the prong was drawn by the vibration.
For concrete the coefficient of elasticity E varies with the amount of stress and diminishes as the ratio of sand and stone to cement increases.
Owing to the yielding of joints when a beam is first loaded a smaller modulus of elasticity should be taken than for a solid bar.
It thus appears that if the amplitude of vibration could be as much as 1 o_2 of the wave-length, the aether would be an excessively rare medium with very slight elasticity; and yet it would be capable of transmitting the supply of solar energy on which all terrestrial activity depends.
The idea of MacCullagh's aether, and its property of purely rotational elasticity which had been expounded objectively by W.
The Latin Church, which, by combining the tradition of the Roman centralized organization with a great elasticity in practice and in the interpretation of doctrine, had hitherto been the moulding force of civilization in the West, is henceforth more or less in antagonism to that civilization, which advances in all its branches - in science, in literature, in art - to a greater or less degree outside of and in spite of her, until in its ultimate and most characteristic developments it falls under the formal condemnation of the pope, formulated in the famous Syllabus of 1864.
A medusa has a layer of muscles, more or less strongly developed, running in a circular direction on the surface of the subumbrella, the contractions of which are antagonized by the elasticity of the gelatinous substance of the body.
This movement is resisted by the torsional elasticity of the suspending wire, and hence a fixed indicating needle attached to the movable system can be made to indicate directly on a scale, the difference of potential between the terminals of the instrument in volts.
To the foregoing may be added the following three additional propositions, so as to form a more complete expression of a physiognomical philosophy: (4) Certain muscles concerned in producing these skin-folds become strengthened by habitual action, and when the skin diminishes in elasticity and fulness with advancing age, the wrinkles at right angles to the course of the muscular fibres become permanent.
On being relieved from picket duty Rostov had managed to get a few hours' sleep before morning and felt cheerful, bold, and resolute, with elasticity of movement, faith in his good fortune, and generally in that state of mind which makes everything seem possible, pleasant, and easy.