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This answer has nothing to do with physics, but I was taught in grade school - and, yes, this was in an actual elementary school text - that the Fahrenheit thermometer was based on the coldest and hottest days in 1714 in Holland where he lived. I have never been able to verify that, so I assume it was false, but the temperatures of zero and 100 do represent ...


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Answering your three questions: He knows the relationship between radius and terminal velocity, but the drops are too small to measure their radius with any accuracy (1 ┬Ám is tiny - looking at such a drop from a distance makes it no more than a speck of light, even with a "micro telescope"). Meauring the terminal velocity, he can deduce the size ...


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$G$ was historically calculated from the Cavendish experiment, involving balls and a torsion balance. The earth's mass was actually calculated before the sun's mass. Using the assumption that the earth was a sphere, its circumference and thus its radius could be determined through geodesy, as was done historically even before Newton. The acceleration of an ...


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I've found an historical detailed description in this book: Controversy and Consensus: Nuclear Beta Decay 1911-1934 by Carsten Jensen , From 1911 to 1934, 23 years, a lot of ping-pong with the experiments and theories went forth and back. I will not try to resume the history and the book deserves a reading. My textbooks, aged, only mention the winning ...


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$\newcommand{\pdv}[2]{\frac{\partial #1}{\partial #2}} \newcommand{\div}[1]{\nabla \cdot #1} \newcommand{\curl}[1]{\nabla \times #1} $ Until Maxwell added some terms to the set of equations they were Gauss' Law, Ampere's Law, Faraday's Law, and the fact that there is no magnetic monopole. The equations then read: $$\div E = \rho / \varepsilon_0$$ $$\div B ...


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The book's "derivation" is unusual. Usually, Plank's energy distribution is derived by considering the energy in a large cavity, which tells you about the energy that would be emitted through a small hole in the cavity. That energy has the blackbody spectrum. I think the book is trying to whitewash away a bunch of details by talking about "oscillators ...


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To begin, lets go over the basics again. Any ensemble of two body decays in which the parents and children have the same masses in each event has a delta-function energy spectrum, or violates at least one of energy- or momentum-conservation. The fact that the beta decay spectrum is broad and continuous implies that at least one of the pre-conditions is ...


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Planck published several works on the theory of blackbody radiation based on different ideas, but generally the use of integer counting of energy he meant to be used for the energy of material oscillators. He did not believe the quantization applied to light itself - he assumed Maxwell's theory with its differential equations and derived his spectral ...



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