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How did scientists plot complicated graphs in the 19th century?

I do not know how exactly was this picture made, but there are at least two methods. The first one is to compute this potential (which is not too difficult), plot sufficiently many points and connect ...
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How did scientists plot complicated graphs in the 19th century?

Adding to Alexandre's answer. My father, educated in the 1930s, used a set of "French curves" like this Secondly ... perhaps the picture in the post was not drawn by Maxwell himself, but by a ...
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How did early scientists know if a current was changing direction? (AC vs. DC)

Daniel Sank is correct; with a magnetized needle on a pivot and a coil of wire you can make a device called a galvanometer with which you can watch current change direction, at least for low ...

Were there serious attempts to model the photoelectric effect classically?

"Serious" in the OP sense is probably too high a bar. In 1900-s the situation was very much in flux as to what classical physics could and could not explain. Even Planck's and Einstein's ...
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How did gyromagnetic ratio come up before quantum mechanics, and who introduced it?

This is a very good question, I wish it got more attention. My answer will only be partial for I had difficulty finding early details on gyromagnetic effect and ratio. The concept comes up every time ...
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What is Heaviside's version of Maxwell's equations?

This gives the four equations in the form Heaviside came up with: $$\varepsilon E = \rho$$ $$\nabla \times E = - \mu \frac{\partial H}{\partial t}$$ $$\nabla \cdot \mu H = 0$$ \nabla \times H = k E +...
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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 ...
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Origin of the Heaviside function?

"Oliver Heaviside ... what he was doing, why he developed his step function"? A short answer is that Heaviside was interested, as a practical electrical engineer, in transient effects in complex ...
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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 ...

How was (non-instantaneous) electric current first discovered?

I will assume "non-instantaneous" means something other than electric discharge in the atmosphere, from animals like eels and torpedo fishes, or electrostatic generators like the Leyden jar or the van ...
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Where exactly did George Brown publish the first paper about Turnstile antennas?

Electronics, (subtitled 'radio, communication, industrial applications of electron tubes ... engineering and manufacture') was published by McGraw Hill. Not a journal per se, more of an industry ...
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