Questions tagged [measurement]
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How sensitive was the frog galvanoscope?
Frog galvanoscope is an instrument for detecting small voltages, made of a frog's leg.
Wikipedia notes:
The instrument is capable of detecting extremely small voltages, and could far surpass other ...
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Did any "classical era" physicist foresee that a theory such as Quantum Mechanics is logically inescapable?
I am interested in knowing if in the era preceding the observations that lead to the advent of Quantum Mechanics, anyone foresaw logically that a theory such as Quantum Mechanics is in a sense, "...
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First attempt to measure speeds using distance divided by time?
Did the ancient Greeks, for example, speak of number of paces per heartbeat? I could see them only saying, something moved with the speed of an arrow or a running horse or a running man but that they ...
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partly a LANGUAGE question - uncia (Latin one-twelfth) is the source of both Inch and Ounce. Does anyone know the Greek or pre-Roman equivalent?
Much as per question - Uncia is the Latin for one-twelfth and thence is used for coin (As),length (Pes),weight (Libra), area (Jugerum) etc from whence derives inch and ounce.
I can find nothing much ...
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History of word gram-atom / gram-molecule?
The terms "gram-atom / gram-molecule" are obsolete nowadays in chemistry and got replaced by the concept of "mole/ Avogadro Number". But recently, I encountered a question that can ...
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Ideas about the speed of light between Galileo and Romer?
I know that the great Galileo made no real progress measuring the speed of light -- he disappointingly suggested that it might be infinite. I read that he concluded (based on his attempts to measure ...
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On the choice of Earth circumference vs diameter to define the meter [closed]
I think this is the appropriate SE to ask about the following, but feel free to tell me otherwise.
As I remember it, the meter is a "human" or "natural" length, because it was ...
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What is the official logo of the BIPM?
The logo on the BIPM's (International Bureau of Weights and Measures) site is this:
However, when I visit the English (and, most importantly, French) Wikipedia articles on BIPM, and also when I ...
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Where is the Troughton scale kept?
The Troughton scale served as the first (de facto) standard of length in the United States, from 1832 until 1856. It is a measurement scale of 82 inches, subdivided to tenths of inches, on a silver ...
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Why is one meter as long as it is?
The metre is defined as the length of the path travelled by light in
a vacuum in 1/299 792 458 of a second
Why is this so? Who decided that 1/299,792,458 of a ...
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When was the speed of a bullet or cannon ball first measured?
I would assume that the early estimates were wildly off and wonder how this measurement was done.
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Why are revolutions per minute (RPM) still used instead of hertz (Hz)?
When did people start using Revolutions per Minute (RPM) to measure motors, engines, other devices and where did the term originate? Why do we continue to use it instead of an SI unit like Hz?
From ...
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How were negative numbers first used in physics?
The use of negative numbers in most of today's calculations is natural. But how did the use of negative numbers began in physics? What physical quantity required the introduction of negative numbers ...
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When and how did usage of the term Centigrade give way to Celsius? Are/were they in fact numerically identical?
Discussion below the question Does the US National Weather Service use Celsius or Fahrenheit? and correction of my original use of "Centigrade" to the modern Celsius lead me here.
For ...
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In the world before thermometers did people use freezing points as a sort of proto-thermometer?
Last night I left a bottle of cleanser in my car, and during the 5-degree night the cleanser turned to a sludge.
This started me thinking.
Lots of people living before the development of the ...
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Why does the US keep survey miles and feet?
The United States adopted the international mile and foot in 1959, but for some reason they decided to keep alongside the older units as survey mile and survey foot. These units are almost equal to ...
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Was the value of the mole invented or discovered in chemistry?
For example, $\pi$ is not an invention, it is a discovery which was natural, that is ratio of the circumference of a circle to its diameter. But when we define a meter it is not a natural value it is ...
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How was the historical definition of the meter used in practice?
The meter was initially defined as $10^{-7}$ times the distance of the north pole to the equator. How exactly was this definition used to fabricate the actual meter sticks from which the standard ...
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How did people measure electric charge at the time of Coulomb?
Around the time that Coulomb gave Coulomb's law, how did people measure electric charge?
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Metre definition using a seconds pendulum
I have always heard that the first and most prominent definition of the metre was to use the length of the seconds pendulum - pendulum with the period of exactly 2 seconds. However, in the end it was ...
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How did the integer degrees angles counting being first adopted in geometry and mathematics? [duplicate]
The purpose of this question is trying to know originally how did counting in integer degrees angles from (one degree to $360$ degrees) being adopted basically in geometry, despite the impossibility ...
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Do astronomers still use decimal time?
Wikipedia states that decimal time - where the time of the day is expressed as a decimal part of the day - "have been used by astronomers ever since [Laplace introduced them]". An example by Herschel ...
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discrepancy between Rømer and Fahrenheit scale
Wikipedia states that Rømer temperature scale initially set 0 °Rø for freezing brine and 60 °Rø for boiling water. (He then slightly changed the scale, but the difference is irrelevant for my purposes)...
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Wavelength definition of the metre
Between 1960 and 1983 the metre was defined as being equal to 1 650 763.73 wavelengths of an orange emission line of krypton-86. How did they actually use that definition? Was it possible to move the ...
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When was sealevel discovered?
Or more broadly when did people start marking everything against a common level? Or say when was it known how many feet Rome was above the sea, or if New Delhi or Chengdu was higher?
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Is it known where Eratosthenes first heard of the "well of Syene"?
The American Physical Society's This Month in Physics History; June, ca. 240 B.C. Eratosthenes Measures the Earth says:
Eratosthenes had heard from travelers about a well in Syene (now Aswan, Egypt)...
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Who is the Westphal behind the Mohr-Westphal specific gravity balance? And how exactly did he improve on Mohr?
I'm a Spanish Physics undergrad, and I was writing a report on an experiment we did on the lab, in which we had to measure a solid's density using the so-called Westphal balance (aka Mohr balance, and ...
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What did the ratio of two magnitudes mean to ancient Greek mathematicians?
My understanding is that magnitudes to ancient Greeks meant the actual line segments and plane regions (not the size of the line segment or the area of the plane region), the concept of ratio was then ...
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How did people count seconds before clocks were invented?
How did people count seconds? How did people count minutes? How come that every second of a clock takes exactly as much time as needed to be 86400 to fulfill 24 hours and 31536000 to fulfill a year? ...
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History of the word "scales" in graphing
I am curious to know who first used the term "scale" in graphing, and what exactly did they mean.
Depending on which dictionary you use, a scale can mean "a coating" or a scale can mean a device for ...
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Lise Meitner's contribution to this experimental apparatus and research effort?
I am reading a NYTimes obituary of Otto Hahn and the discovery of fission, and I've asked in physics SE about the function of the apparatus shown in that article.
The system shown demonstrated the ...
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History of cubit - Galilei, Kopernik, Newton
Can cubit from Galileo Galilei books " Dialogue Concerning the Two Chief World Systems", "Two New Sciences", Newtons "Philosophiae Naturalis Principia Mathematica" or Mikołaj Kopernik books convert to ...
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When was the measurement problem solved?
I have been looking into the measurement problem that arises when considering different interpretations of quantum mechanics. Nowadays it seems to be considered a solved problem (in fact some people ...
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Who first measured the distance to the Moon? How was it done?
Who first measured the distance to the Moon? How was it done? I think it had to happen after Newton, but I am not sure.
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Why does the statute mile have the length that it has?
Why was our (statute) mile established as it was?
This happened in 1593, by the order of Elizabeth I which said:
"A Mile ſhall contain eight Furlongs, every Furlong forty Poles, and every Pole ...
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