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It happened long before Newton. In the second century BC Hipparchus used lunar parallax to calculate a value for the minimum and maximum distance of the earth and moon. His results are very close to the modern calculation of this distance. You can read about it here: Toomer G.J. (1974), "Hipparchus on the Distances of the Sun and Moon." Archives for the ...


9

Ancient Greeks painstakingly avoided negative numbers, although they could have come handy in astronomical calculations and number theory, among other places. Brahmagupta in Correctly Established Doctrine of Brahma (c. 630 AD) uses the language of "fortunes" and "debts", which suggests the merchant origin of the negative number concept, but that remains a ...


8

This is an ill defined question. It can be interpreted as "Who was the first to TRIED to measure the distance to the Moon", or "Who was the first to give a correct number", and what is counted as correct number. And even this does not define the question precisely. The crucial question: "in what units"? It is relatively easy to measure the distance in ...


5

Wikipedia refers to the Julian Date system, which is used, primarily by astronomers, to this day. It is convenient due to irregularities in the standard calendar periods. The Julian days give a continuous count of days since the beginning of the Julian Period, introduced by Scaliger in 1583, i.e. since 1 January 4713 BC (Julian calendar), originally for the ...


5

To a certain extend, the measurement problem (MP) is indeed philosophical, in the end, it still comes down to which interpretation you prefer. However, there are also of course also certain physical results, which come into play here. These are also highly relevant to the various interpretations, which I will try to put in appropiate context. The keyword in ...


4

Issues regarding ancient measure systems are not easy to manage... Galileo Galilei, in Discorsi, uses braccia; the "old" translation by Crew & Di Salvio uses: "cubits". A braccio in Florence was: 583 mm. In ancient Rome: according to Vitruvius, a cubit was equal to $1 \frac 1 2$ Roman feet or 6 palm widths, which is 443.8 mm (17.47 in). According ...


3

The unabridged Oxford English dictionary clarifies the "when" part of the question. Also consult the paper in Nature (1949) https://www.nature.com/articles/163427a0 for the historic discussion (paper is open access). However, the modern reference point is triple point of water, "The Celsius scale is defined using the T.Pt. = 0.01 °C with 1 °C made identical ...


3

We often forget that even the minute is not an SI unit, only the second and its decimal multiples and fractions are. It is a leftover of the sexagesimal system (base 60), whose use predates the decimals by many centuries, and goes back to the ancient Babylon. So are the angular degrees. Heinrich Hertz was born in 1857, and the International Electrotechnical ...


3

The OED writes this: "Originally: the Roman unit of distance of 1000 paces (mīlle passus or passuum), reckoned to have been about 1618 yards (approx. 1479 metres). Hence: a unit of distance derived from this used in the British Isles and in other English-speaking countries, and now equal to 1760 yards (approx. 1609 metres). Frequently with a prefixed ...


3

Electricity has nothing to do with the question. Clocks which could count minutes and seconds were purely mechanical and precise mechanical clocks (which could count seconds reliably) were invented in 18th century. Until 1970s most wristwatches were mechanical. They are available nowadays as well but good ones are expensive. People did not count minutes and ...


3

The earliest extant description of Erathostenes' method is found in a book by Cleomedes written in the 1st century BC, and no wells are mentioned at all, if it's true that it's stated that whenever the Sun, 'being in Crab at the summer solstice, the pointers of the sundials in Syene throw no shadows...'


3

Quoth H. R. Jenemann, Die Geschichte der Dämpfung an der Laboratoriumswaage (1997, p. 240): In 1879, Georg Westphal filed a patent in Celle for a scale which was distinguished by various innovations and featured a similar brush lock19. With this special scale, the scale carrier had no connection to the beam of the scale; it could swing freely about its ...


3

Fowler's Ratio in Early Greek Mathematics is a standard reference on the subject, see also his book Mathematics Of Plato's Academy (both are freely available). Book V, Definition 3 of Euclid's Elements reads: "A ratio (logos) is a sort of relation in respect of size between two magnitudes of the same kind". Thus, ratios of magnitudes were indeed non-...


3

There are much easier ways to measure a wavelength than by "tromboning" an interferometer. A simple two-slit grating, for example, will give you a pretty decent measurement. You don't need to measure a "meter's worth" of light, just run an experiment where the output data (such as a diffraction pattern) can be used to calculate the wavelength to high ...


2

It was actually done with a "tromboning" Michelson Interferometer (https://www.bipm.org/en/measurement-units/history-si/former-prototype-metre.html) In 1892 by Michelson. He measured a distance of 10cm to an accuracy of ± 0.00004 mm using a Cadmium lamp . The 1960 re-definition with Krypton used the same data - it was just a matter of measuring the ...


2

See : Bartel van Der Waerden, Science Awakening, Oxford UP (original ed, 1950), page 37 : The sexagesimal system was taken over by the Semitic Babylonians from their predecessors, the Sumerians. This remarkable cultural group, which had also invented the cuneiform script, dominated southern Mesopotamia during the third millenium B.C. Regarding $\pi$, ...


2

The above photo was reproduced in the biography: Lise Meitner, A life in Physics, by Ruth Lewin Sime; University Of California Press,1996, ISBN 0-520-20860-9. A brief description of the parts is given on page 371, bottom and 372 top. The attached photo, describing some of the components, is from those included with the text.


2

Not really. Using multiple liquids to register a single temperature probably would have been impractical, but crude thermometers appear already in antiquity. Philo of Byzantium c. 240 BC used a tube from a hollow sphere to a jug of water. When the sphere was in the sun bubbles were released as air expanded out of the sphere, when moved to the shade, the ...


1

Perrin originally defined the Avogadro number as the number of atoms in one gram of hydrogen (later it was redefined as the number of atoms in 12 grams of carbon-12). As such, it was certainly discoverable from measurements. However, picking grams, or hydrogen was not "natural". Neither was picking circles and diameters in the definition of $\pi$. Once they ...


1

Once the definition in terms of the length of the meridian was accepted, the French sent several expeditions to measure the meridian. On the basis of these expeditions, the reference meter (a stick of a special alloy, which has very little thermal expansion) was made and kept under controlled conditions. Later, when more precise measurements of Earth were ...


1

People did not. They generated and stored static electricity, but measuring it, other than by how strong the electic shock felt, was not yet done. Coulomb was the one who invented a way to do it in 1785. For this he used a device called torsion balance. John Michell used it earlier to measure gravity, but Coulomb re-invented the idea, and made it famous. ...


1

First of all, the amplitude of the pendulum swing has a very small effect until you get to rather large swings. That's the beauty of the sine function. :-) . Next, it took rather a while for science to develop the concept of repeatability, let alone repeating this precise pendulum measurement in several locations -- and observing a repeatable difference. ...


1

You probably mean MSL, which is Mean Sea Level. In order to calculate the predicted height of a tide we work with amplitudes relative to a mean level as the tide approximates a sinusoidal behaviour. It was therefore necessary to measure the level of the sea surface relative to some arbitrary reference level, called Chart Datum (C.D.). As the tides vary in ...


1

How did people count seconds before clocks were invented? In general, they didn't, because there was no need to to so. The need for accuracy to the level of a second or less is a very recent need. Before the invention of trains and telegraphs, there was no need for even hour level accuracy, let alone minute or second level accuracy. Whether the roads were ...


1

There are (at least) three different English words written and pronounced “scale”. The “scale” of a fish or reptile is a borrowing from an Old French word adopted from a Germanic form cognate with the English word “shell”. A "scale" for weighing is originally a "bowl", borrowed from Old Norse. “Scale” in its various mathematical usages is borrowed from ...


1

This problem is a philosophical problem. And philosophical problems are almost never solved. This is probably the reason why some physicists are annoyed with it. Strictly speaking this is not a physics problem. EDIT. There are different opinions on what constitutes physics and what does not. And this changes with time too. To begin with, would you care to ...


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