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41 votes
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Timeline of measurements of the electron's charge

If anyone's still reading this thread, here's a few more data points that appear to back Feynmann's interpretation. Erik Bäcklin, Nature vol 123, no. 3098, p. 409 (1929): $1.59875 \cdot 10^{-19} \pm ...
Anonymaus's user avatar
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14 votes

How did J. J. Thomson establish the particle nature of the electron?

The idea that matter was made up of "primordial" particles, and currents in metals consisted of them was well established by then. Stoney suggested the name "electron" in 1891, and Lorentz's theory of ...
Conifold's user avatar
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9 votes
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Could scientists of Newton's time have explored the limits of his laws of motion?

At the time of Newton, the scientists could NOT detect any deviation of the Newton's laws from reality. As we know now, the only visible effect of this deviation in the Solar system is the anomalous ...
Alexandre Eremenko's user avatar
9 votes

How did Stern or Gerlach, of Stern-Gerlach experiment, create individual silver atoms? How were they accelerated?

Atomic spectroscopy was very advanced 100 years ago (1920s) and we must appreciate their intelligence. If a metal like silver is being heated to the extent of boiling in high vacuum, all you get is ...
AChem's user avatar
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9 votes

Have there been instances in physics where different scientists have interpreted the same data differently?

The comments correctly say that this happens all the time. For a recent example, you can see my answer to: Can a highly-cited published paper have this type of error? I will explain here some details ...
Nike Dattani's user avatar
8 votes

What did it historically mean in physics for something to "exist"?

To not be measured is not to have any behavior. No dynamic is induced on any other system in the universe by this object (Rosen 1978). Objects without behavior do not exist. Their behavior is that ...
Gottfried William's user avatar
8 votes

How did Henry Cavendish deduce the inverse square law in electrostatics from his experiment in 1772?

Newton proved that if the attraction obeys the inverse square law, then the force inside a uniformly charged sphere is zero. It follows from the description that you give that Cavendish used the ...
Alexandre Eremenko's user avatar
8 votes

Does anyone know of any examples of the Magnus effect in a real battle?

I am afraid nobody noticed it, because nobody could have noticed it. A deviation is only a deviation when one has something that it is a deviation from. To "notice" the Magnus effect one has to ...
Conifold's user avatar
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8 votes
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Significance of Higgs model used in Glashow-Salam-Weinberg theory

This is precisely why this question belongs to HSM.SE with both feet! Your vision of what happened is deeply misleading, possibly requiring time travel. Recall the GWS 79 prize citation: "for ...
Cosmas Zachos's user avatar
7 votes
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Who really discovered/invented the Hooke's law?

Proportionality law for elastic forces is one discovery at which Hooke did arrive first. He describes it in De Potentia Restitutiva (1678): ”The Power of any Spring is in the same proportion with ...
Conifold's user avatar
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7 votes
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How did Galileo know that objects rolling down a ramp was an accurate model for free fall?

From: Discourses and Mathematical Demonstrations Relating to Two New Sciences (Italian: Discorsi e Dimostrazioni Matematiche Intorno a Due Nuove Scienze), published in 1638. See: Engl.transaltion by ...
Mauro ALLEGRANZA's user avatar
7 votes
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How did Newton prove his third law of motion?

It was not "the experiment". First, Newton considered "his" laws to be "common knowledge" already "abundantly" confirmed and accepted by experts (he names ...
Conifold's user avatar
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7 votes
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When was the geometric structure of a water molecule discovered?

Császára et al. J. Chem. Phys. 122, 214305 (2005) has a nice table of determination of the bond angle of water per year (missing probably Linus Pauling first predicting 90° from approximations in ...
Mauricio's user avatar
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6 votes
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Which physicist defended the Superconducting Super Collider?

Fermilab director R. R. Wilson’s Congressional Testimony (April 17, 1969, p. 113): SENATOR PASTORE. Is there anything connected in the hopes of this accelerator that in any way involves the security ...
Francois Ziegler's user avatar
6 votes
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Why is the Michelson–Morley experiment so much more famous than its rivals?

Because it was the most accurate. The use of interferometers to measure length deviations eliminated the concern that the ether wind didn't register because the instruments were too blunt, or because ...
Conifold's user avatar
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6 votes

How was the idea of observation error introduced?

Astronomers had to deal with experimental errors to parametrize their geometric models at least as early as Hipparchus, and possibly earlier. There are some techniques and ad hoc methods that can be ...
Conifold's user avatar
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6 votes
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How did Henry Cavendish deduce the inverse square law in electrostatics from his experiment in 1772?

Alexandre Eremenko's answer is great, but I figure the page could benefit from an explanation of the method in general. Cavendish's Experiment The question Cavendish was facing was this: Given that ...
Sam Gallagher's user avatar
6 votes

Significance of Higgs model used in Glashow-Salam-Weinberg theory

It is called verification from experimental results. The GSW theories fitted mathematically the observed particle zoo symmetries and explained the approximate symmetries seen in the data. The Higgs ...
anna v's user avatar
  • 169
6 votes

Do Nobel prizes tend to go to theorists or experimenters?

Statistically, experimenters are typically favored. One reason is that theories are only Nobelized when confirmed, and that may take too long for getting the prize. Another is that new experimental ...
Conifold's user avatar
  • 77k
5 votes
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How were atomic weights originally measured?

Do you know about Lomonosov's and Gay Lussac's contribution in understanding of chemical reactions and Avogadro's contribution? These three chemists contributed to a great extent to the understanding ...
user118008's user avatar
5 votes

High voltage / current sources in 19th century cathode ray experiments

In order to obtain a nonpulsating power source some early investigators used Wimshurst or similar static electricity generators, or batteries of many small storage cells. (The discovery of the ...
jkien's user avatar
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5 votes
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What was this experiment tainted by the observer effect?

This is the story of the "discovery" of "N Rays", as described in a Wikipedia article. The gist of the story told there is as follows: In 1903 the physicist Prosper-René Blondlot (1849 – 1930) ...
kimchi lover's user avatar
  • 2,555
5 votes

Did Ptolemy and other Greek scientists actually measure the distance to the Sun?

No, they did not. Several methods were proposed but they do not give "correct" distances. Of course, all depends on the exact meaning of the word "measure" and "correct". But their estimates were ...
Alexandre Eremenko's user avatar
5 votes
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Why is it said that Marie Curie died due to her work but the same isn't said for Fermi?

Is it simply that the causation between the work and the disease is more clear in the case of Curie but not Fermi? Marie Curie died of Aplastic anemia which was most likely due to exposure to ...
SBoZon's user avatar
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4 votes
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Was Newton aware his theory of gravity had flaws?

See Perihelion precession of Mercury: Mercury deviates from the precession predicted from these Newtonian effects. This anomalous rate of precession of the perihelion of Mercury's orbit was first ...
Mauro ALLEGRANZA's user avatar
4 votes

Could scientists of Newton's time have explored the limits of his laws of motion?

One of the main criticisms of Newtons theory of Gravitation was philosophical; in that his theory incorporated action at a distance; this criticism was something that Newton was very much aware of, ...
Mozibur Ullah's user avatar
4 votes

How did Milikan know that oil drops would acquire only few electron charges?

I think the way Millikan deduced the number of electrons was, aside from the current state of knowledge as Conifold relates, by taking lots and lots of measurements (certainly that's what I did when ...
Carl Witthoft's user avatar
4 votes
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When was it first noticed, or demonstrated, that radioactive material became warm?

I found the following at an AIP site on Marie Curie, apparently a copy of an article of hers in Century Magazine, pp 461-466 (January 1904). It appears to be a non-technical journal: Radium ...
Jon Custer's user avatar
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4 votes
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How was it determined that the photoelectric effect is independent of the intensity of light?

There was no need to measure the intensity directly to determine that the photoeffect is independent of it. One could vary intensity by moving the metal plate closer to or further away from the source....
Conifold's user avatar
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