Synthesized answer
The passages indicate that the variation of an electron's mass with speed and radioactivity appeared to challenge the conservation laws because they suggested that mass might not be constant. Specifically, experiments by Kaufmann showed that the ratio of electric charge to mass (e/m) for negative particles varied with speed, implying that mass changes with velocity [2]. This directly conflicts with the classical law of conservation of mass, which assumes mass is an invariant quantity. Similarly, radioactivity involves particles moving at velocities near the speed of light, where such mass changes become significant [2].
These observations could also appear to challenge the law of conservation of energy. If mass is not constant but varies with speed, the traditional relationship between mass and energy might be called into question, potentially undermining the separate conservation of mass and energy as independent laws. The text notes that these phenomena created doubt about "the exact validity of some of the most general laws of nature" [1], but Lewis aims to show that a new system of mechanics can be constructed that upholds the three great conservation laws—energy, mass, and…
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From the book
ose fundamental principles of the mechanics of ponderable matter which have remained unaltered since the time of Newton. The recent experiments which indicate a change in the mass of an electron with the speed, together with the phenomenon of radioactivity, have in some minds created a doubt as to the exact validity of some of the most general laws of nature. In the following pages I shall attempt to show that we may construct a simple system of mechanics which is consistent with all known experimental facts, and which rests upon the assumption of the truth of the three great conservation…
elocity of the fastest cannon-ball would, according to this equation, gain in mass by less than one millionth of a gram. It is obvious that, except in those unusual cases in which we deal with velocities comparable with that of light, our non-Newtonian equations are identical with those of ordinary mechanics far within the limits of error of the most delicate experiments. Recently, however, it has been possible to study, in the negative particles emitted by radioactive substances, bodies which sometimes move with a velocity only a little less than that of light. In a series of remarkably…
ctness of this view may be decided by an experimental study of the mass of a positive or α particle at different speeds. According to the ordinary view, the mass of such a positive particle as issues from a radioactive source is chiefly that of its "ponderable" matter and only to a very small extent "electromagnetic mass." It would therefore be generally assumed that at the highest velocity of the particle, about one-tenth of the velocity of light, it would have substantially the same mass as at rest. According to our view, on the other hand, the mass of this or any other particle would…
an mechanics and assuming the conservation laws of mass, energy, and momentum, a new system of mechanics is constructed. In this system momentum is mv , kinetic energy varies between 1/2 mv² at low velocity and mv² at the velocity of light, while the mass of a body is a function of the velocity and becomes infinite at the velocity of light. The equation obtained agrees with the experiments of Kaufmann on the relation between the mass of an electron and its velocity. It is, moreover, strikingly similar to the equations that have been obtained for electromagnetic mass. The new view leads to an…
← A revision of the Fundamental Laws of Matter and Energy ( 1908 ) by Gilbert Newton Lewis → related portals : Relativity Philosophical Magazine, 1908, 6 16 (95): 705-717, Online 412006 A revision of the Fundamental Laws of Matter and Energy 1908 Gilbert Newton Lewis THE LONDON, EDINBURGH, AND DUBLIN PHILOSOPHICAL MAGAZINE AND JOURNAL OF SCIENCE. [SIXTH SERIES.] NOVEMBER 1908. LIX. A Revision of the Fundamental Laws of matter and Energy. By Gilbert N. Lewis . Ph.D., Associate Professor of Physical Chemistry, Massacussets Institute of Technology, Boston . R ECENT publications of Einstein and…
More questions about this book
- Lewis states his intention to "modify those fundamental principles of the mechanics of ponderable matter which have remained unaltered since the time of Newton." Explain in your own words what makes such a drastic revision necessary at this time, citing specific experimental and theoretical advancements mentioned in the text.
- Lewis proposes to build a "simple system of mechanics" consistent with known facts and resting on the conservation laws. Articulate, as if explaining to a peer, the historical significance of *reaffirming* the conservation of mass and energy in 1908, given the scientific landscape described in the excerpt.
- Describe the phenomenon of light pressure and how its experimental verification, combined with the law of conservation of momentum, "inevitably leads" to the conclusion that a beam of light possesses momentum. Why is this particular insight crucial for Lewis's revision of fundamental laws?
- Considering Lewis's 1908 publication date and his reference to Einstein, how does this "revision of the Fundamental Laws of Matter and Energy" reflect the broader conceptual revolution in physics occurring at the beginning of the 20th century? What previously held assumptions about the nature of matter and energy are being challenged and potentially integrated?