This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1874 Excerpt: ...of the water in the well is relieved by making a vacuum above it, the air--an external agent--exerts force and pushes the water up the pipe. It is the air in the receiver itself which in some way causes a portion of it to rush violently out at the valve, giving to this portion a sensible kinetic energy. And accordingly ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1874 Excerpt: ...of the water in the well is relieved by making a vacuum above it, the air--an external agent--exerts force and pushes the water up the pipe. It is the air in the receiver itself which in some way causes a portion of it to rush violently out at the valve, giving to this portion a sensible kinetic energy. And accordingly, it has long been known (though this explanation was not thought of till recently) that cold is produced; that is, heat disappears. We must now look out for some manageable shape of experiment to enable us to measure the quantities concerned. The action is obviously precisely the same when air compressed in a vessel, so as to be denser than the surrounding air, is then allowed to rush out by turning a stopcock. Accordingly, the vessel is found to be cooled, and the quantity of heat lost may be ascertained by keeping the vessel immersed in a water-bath, and seeing how much water it can cool by 1. But in this (an old experiment) we take no account of what happens to the air that escapes. Mr. Joule varied the experiment by having two vessels, connected by a pipe and stopcock. In one the air was very much compressed; in the other, it was in its usual state of atmospheric pressure. They can be either placed each in a separate water-bath, provided with a thermometer, or both in one. When the communication is opened air rushes from one vessel to another. If the cock be closed before the density has become uniform in both, the air that was in violent motion in the second vessel almost immediately comes to rest. Kinetic energy, which had been produced at the expense of heat (as we saw), has now disappeared, and therefore, according to our previous investigations, heat should appear in its place. And it does so. When the two vessels are in separate bat...
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Add this copy of An Elementary Exposition of the Doctrine of Energy to cart. $61.95, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2019 by Wentworth Press.
