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30

One early invention for storing energy was a basin above the level of the river. It was filled with water when the water in the river was high, and then, when the water in the river was low, it was allowed to flow to the fields from the basin. Such a basin could also be filled manually. Such devices were used in ancient Egypt, as a part of their irrigation ...


23

The controversy was ostensibly over what gets to be the "true quantity of motion", momentum or vis viva (kinetic energy), with Newton and Leibniz on the opposing sides. While there was some philosophical angle at first, a "skillful attack by Leibniz against an inadequate concept, $m|v|$, and its description of the world", it quickly deteriorated into a ...


21

This is probably not what you were thinking of but "the earliest invention that allowed energy to be stored and released after a delay even it's just a short time" was a stone. I can store energy in it briefly by flinging it at your head (kinetic). I can store energy in it even longer by putting it on a cliff above your head (potential). Stone ...


11

Let me clarify first that there are deep conceptual issues with what $E=mc^2$ means, and what it means to verify it. That energy contributes to inertial mass was known before Einstein. In 1900 Poincare showed that electromagnetic field has momentum, hence effectively mass, and implicitly gave it as $E/c^2$. Austrian physicist Hasenöhrl even wrote explicitly $...


10

Agriculture The purpose of farming is to harness the freely available energy from the sun, and convert it into a form that can fuel the human body. Agriculture enabled significant food surpluses, which is simply a form of energy storage. Similar to how a flywheel stores mechanical energy which can be used later, food surpluses store chemical energy which can ...


6

This depends on which objects you have in mind and who you would call a scientist. There was a broad consensus in the ancient Greek natural philosophy that superlunar objects, like the stars and planets, were moving on their own steam, pardon, divine nature, and uniformly along circles at that. Early mathematical astronomers accepted this conviction to such ...


6

Gaspard-Gustave Coriolis and Jean-Victor Poncelet used the name "quantité de travail" (quantity of work) and "travail mécanique" (mechanical work) to denote the kinetic energy. I guess that this (the term "travail") could be the origin of the symbol $T$. See at the end of https://en.wikipedia.org/wiki/Vis_viva (Be patient for my superficiality, I am very ...


5

There are several themes in Huygens' unpublished paper De motu corporum ex percussione ("On the motion of bodies out of collisions"), but maybe the most significant is that he frequently investigates a specific or extreme case (where some factor is zero, one, or infinity) first, and then guesses about a general case which might have those at its boundary. ...


5

("How did Huygens derive the conservation law for of kinetic energy?") Huygens in 'The Motion of Colliding Bodies' (English translation) contributed ingenious reasoning, mathematics and thought-experiments based on physical assumptions. But this work was all about the collisions of a particular kind of body -- supposed and idealized at some distance away ...


5

The "mathematics" was a combination of experiments with falling bodies, imaginative thought experiments, common sense, and geometric reasoning. Part of it is explained in the book. Galileo found that $v^2$ at the time of impact is proportional to $h$. Torricelli argued that when two bodies are linked together and freely move, but only in a vertical ...


5

I’m pretty sure Lagrange started this, in Méchanique analitique (1788, p. 224; 1809, p. 263; 1811, p. 311; 1815, p. 2): his predecessors mostly worked with the vis viva ($=2T$) instead. (As to why he chose the letter $T$, no idea. Words like kinetic, energy, work, appeared only later.)


5

I suspect what you really are after is the electron's mass, since we can then "easily" get its energy via an obscure :-) equation developed by some fellow named Einstein. The path thru measuring the charge-to-mass ratio, followed by some famous oil-drop experiments, is discussed pretty well in a physics.SE page.


4

According to the OED, Clausius coined the German word "virial" (from vīs force, strength): a. In Clausius' kinetic theorem of gases: (see quots.). virial theorem, the theorem that for a steady-state system of particles obeying an inverse square law of force, the time-average of the kinetic energy equals the time-average of the virial; or equivalently, ...


4

You can see : Agamenon Oliveira, A History of the Work Concept: From Physics to Economics, Springer (2014). Also interesting : Danilo Capecchi, History of Virtual Work Laws: A History of Mechanics Prospective, Birkhauser (2012).


4

I must put up a clarifying answer. They groped towards different concepts and talked past each other, in the modern perspective. Much of what we call Newtonian mechanics is due to Euler, who called it such in his early papers on the topic, but Euler wrote after the controversy. (See Truesdell) The problem is, as is clearly seen from the primary texts of ...


4

According to this page, charcoal was in use circa 3750 BCE. That's an energy storage medium, although perhaps not the class of energy-release you were thinking of.


4

The controversy was not so much about the tension between vis viva and mechanics, as about what is the "true" quantity of motion, vis viva or momentum, and what is the "metaphysical" basis upon which mechanics is to be built, vis viva or Newton's force (aside from multiple other side issues that got entangled with it, see What was the vis ...


3

Tree limb. Before humans became ground bound, they used tree limbs to catapult themselves to the next tree. But seriously, probably a stone, then a stone attached to a stick, then a stone attached to a stick shot from a string attached to a stick. Do I get voted off the island? I just got here.


3

How about good-old fashioned pit traps? If 'stored energy' is something where you input work ahead of time and then it is expended at a later date for a use, a pit trap is a perfect example. While digging the pit, you are removing a great deal of material, and effectively 'storing' gravitational potential energy in the difference between the height of the ...


3

It is not that it had to wait to be "established", it is obtainable from what was known by trivial algebra, but rather that it had to wait for a reason to write it that way. In the early years of relativity the concept of the "electromagnetic mass" of electron was prominent, which suggested that said mass is velocity dependent. It was at ...


3

In theory, relativistic mass was preceded by the "electromagnetic mass" introduced by J.J. Thomson in 1881, and further developed by Heaviside (1888), Searle (1897), Poincaré (1900), Abraham (1902), Lorentz (1904). https://en.wikipedia.org/wiki/Electromagnetic_mass In practice, the first experiments precise enough to measure such effects were conducted by ...


3

This is a very interesting and complex topic that is far from closed. Here are some of the sources I have found. Energy the subtle concept, by Jennifer Coopersmith, is probably the book you are looking for. However, if you get interested in more critical accounts, continue reading. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780198716747.001....


3

In Principia Newton presents a picture based on forces rather than energy and momentum, and he did not have the concepts of vector and of mechanical energy at his disposal. Moreover, Newton opposed Leibniz's idea of putting kinetic energy ("vis viva") at the center of dynamics on philosophical grounds, because he considered forces to be more fundamental. ...


3

There is a second sentence to the quote:"The energy of the universe is constant. The entropy of the universe is increasing". The conservation of energy law. The second law of thermodynamics. The quote became famous because from the conjuction of the two conclusion about the heat death of the universe appears to follow. The idea was expressed earlier by ...


2

In 1932 Landau speculated that the conservation of energy is not valid in neutron stars and appealed to the authority of Niels Bohr[1]: Following a beautiful idea of Professor Niels Bohr’s we are able to believe that the stellar radiation is due simply to a violation of the law of energy, which law, as Bohr has first pointed out, is no longer valid in the ...


2

Actually, it wasn't Dirac who first found that relation. It was already used by Planck as early as in 1906 while deriving the Hamiltonian equations of motion Planck: The Principle of Relativity and the Fundamental Equations of Mechanics (1906). He first gave the Lagrangian function $$ (1)\quad L={\dot {x}}{\frac {\partial H}{\partial {\dot {x}}}}+{\dot {y}}{\...


1

It was a side effect of the vis viva controversy described in What was the vis viva controversy, including its philosophical aspects? about what to call the "quantity of motion", momentum (vis mortua, dead force) or kinetic energy (vis viva, living force). Since the conservation of $mv^2$ in elastic collisions led to singling out vis viva as a ...


1

Let us consider the following info on developments prior to 1905. Before 1905 (The forthcoming of $E = mc^2$) 1881 J. J. Thompson proposed that a charged conductor in motion increases its mass by $\frac{4}{15} e^2/a$ 1904 H. A. Lorentz proposed that $m_L = m_0 (1 – v^2/c^2)^{-3/2}$ based on deformable spherical charge. 1904 Hasenöhrl derived an apparent ...


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