Questions tagged [conventions]
A convention is a set of agreed, stipulated, or generally accepted norms. It typically helps common efficiency or understanding but is not required, as opposed to a strict standard or protocol.
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Why was carbon-12 chosen for the atomic mass unit?
The atomic mass unit is defined as 1/12th the mass of a carbon-12 atom. Was there any physical reason for such a definition? Were they trying to include electrons in the atomic mass unit?
Why not ...
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Why is it "bad taste" to have a dimensional quantity in the argument of a logarithm or exponential function?
I've been told it is never seen in physics, and "bad taste" to have it in cases of being the argument of a logarithmic function or the function raised to $e$. I can't seem to understand why, although ...
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Why does public mains power use 50-60 Hz and 100-240 V?
Is there a physical reason behind the frequency and voltage in the mains electricity? I do not want to know why exactly a certain value was chosen; I am rather interested to know why that range/order ...
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Why is the charge naming convention wrong?
I recently came to know about the Conventional Current vs. Electron Flow issue.
Doing some search I found that the reason for this is that Benjamin Franklin made a mistake when naming positive and ...
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Should zero be followed by units? [duplicate]
Today at a teachers' seminar, one of the teachers asked for fun whether zero should be followed by units (e.g. 0 metres/second or 0 metre or 0 moles). This question became a hot topic, and some ...
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What are the proposed realizations in the New SI for the kilogram, ampere, kelvin and mole?
The metrology world is currently in the middle of overhauling the definitions of the SI units to reflect the recent technological advances that enable us to get much more precise values for the ...
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Difference between $\Delta$, $d$ and $\delta$
I have read the thread regarding 'the difference between the operators $\delta$ and $d$', but it does not answer my question.
I am confused about the notation for change in Physics. In Mathematics, $\...
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Why is the partition function called ''partition function''?
The partition function plays a central role in statistical mechanics.
But why is it called ''partition function''?
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Identification of particles and anti-particles
The identification of an electron as a particle and the positron as an antiparticle is a matter of convention. We see lots of electrons around us so they become the normal particle and the rare and ...
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Why is gravitational potential energy negative, and what does that mean?
I usually think of gravitational potential energy as representing just what it sounds like: the energy that we could potentially gain, using gravity. However, the equation for it (derived by ...
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Square bracket notation for dimensions and units: usage and conventions
One of the most useful tools in dimensional analysis is the use of square brackets around some physical quantity $q$ to denote its dimension as
$$[q].$$
However, the precise meaning of this symbol ...
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Can units be plural? [duplicate]
I was in a conversation with my senior engineer where he kept on insisting that we can use plural when we write down any unit. I argued that it is not the 'common' practice or even throughout my whole ...
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Why do we use the electron volt?
Why do we use the electron volt?
Why did it come to be the electron volt and not, say, just a prefix of the joule, like the nanojoule?
Does the electron volt represent anything particular as far as ...
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Symbols of derivatives
What is the exact use of the symbols $\partial$, $\delta$ and $\mathrm{d}$ in derivatives in physics? How are they different and when are they used? It would be nice to get that settled once and for ...
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Why is the potential energy equal to the negative integral of a force?
Why is the potential energy equals to the negative integral of a force? I am really confused with this negative sign. For example, why there is a negative sign in the gravitational potential energy ...
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