The correlation of physical forces: being the substance of a course of lectures delivered in the London Institution, in the year 1843 / by W.R. Grove.

  • Grove, W. R. (William Robert), 1811-1896.
Date:
1846
Catalogue details

Licence: Public Domain Mark

Credit: The correlation of physical forces: being the substance of a course of lectures delivered in the London Institution, in the year 1843 / by W.R. Grove. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

    18/64 (page 10)
    the moving body, and which when this impinges on another body, ceasing to exist as gross palpable motion, continues to exist as heat. Thus, let two bodies, A and B, be supposed moving in opposite directions (putting for the moment out of the question all resistance, such as that of the air, &c.), if they pass each other without contact, each will move on for ever in its respective direction with the same velocity, but if they touch each other, the velocity of the movement of each is reduced, and each becomes heated; if this contact be slight, or such as to occasion but a slight diminution of their velocity, as when the surfaces of the bodies are oiled, then the heat is slight; but if the contact be such as to occasion a great diminution of motion, as in percussion, or as when the surfaces are roughened, then the heat is great, so that in all cases, the resulting heat is in direct proportion to the diminished velocity. Where instead of resisting and consequently impeding the motion of the body A, the body B gives way, or itself takes up the motion originally com- municated to A, then we have less heat in proportion to the motion of the body B, for here the operation of the force continues in the form of palpable motion; thus the heat resulting from friction in the axle of a wheel is lessened by surrounding it by rollers, these take up the primary motion of the axle, and the less, by this means, the initial motion is impeded, the less is the resulting heat. Again, if a body move in a fluid, the heat produced is very trifling, because the particles of the fluid themselves move, and con- tinue the motion originally communicated to the moving body; for every portion of motion communicated to them this loses an equivalent, and where both lose, then an equivalent of heat results. As the converse of this proposition it should follow, that the more rigid the bodies impinging on each other, the