# Tag Info

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The answer depends on the exact definition of the set of fundamental constants, as well as on the choice of base units of a given system of units. A look at the NIST page Fundamental Physical Constants --- Complete Listing shows that they list too many fundamental constants to allow assignment of a unit value to each of them, within the International ...

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You can use "natural units" to set some of the fundamental constants (usually $\hbar$, $c$, Coulomb's constant) equal to one, but this fixes the values of other constants as values other than one. For example, by setting $\hbar$, $c$ and $k_e$ equal to one, you can find the elementary charge, $e$, in terms of the fine structure constant, $\alpha$. \alpha=...

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The unit of torque is N m / rad.

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Your metric either contains explicit factors of $c$ that match the units between space and time or you use units in which $c=1$ in which case space and time have the same units “naturally”. That’s the answer about consistency. As to what the overall unit is, it doesn’t matter. That’s just an overall rescaling, which has no physical consequence. I’ve worked ...

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Everything!!! Natural units just make your life simpler, is like removing every unnecessary conversion factors which need to be added, helps by making the equation look smaller, and can easily give back the final equation just by dimensional analysis. Okay you might be wondering what dimensional analysis has got to do with natural units. Well let's see an ...

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$1T= 1\frac{Vs}{m^2}$ corresponds to $\frac{299.792}{ce}\frac{MeV}{m}$ ($c$ stands for speed of light and $e$ for the elementary charge) as it can be easy checked by reducing the fraction with $c=0.299792\cdot 10^9\frac{m}{s}$ and $e$ ($\frac{MeV}{e}=MV)$.

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I think there's a fundamental problem with how the materials react under a point/local load. You can't do hardness testing on rubber with a pointy sharp probe that's going to split the material open, and you'd have to produce a huge force to push a dull/blunt probe into a hardened steel sample far enough to be able to measure it with the precision available ...

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The answer by Michael Deckers provides some useful references, but is not completely correct. The Rapport BIPM-2019/05 linked in that answer does give Spectral luminous efficiency functions in sections 4.1 through 4.3 and tables 1 and 2 — for all of photopic (2° and 10° FOV versions), scotopic and mesopic vision, the latter for varying levels of adaptation....

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There is an error in the above: "From Ohm's law V=IR", Ω=V/A=(J/C)/(C/sec)=(Nm/C)/(C/sec)=Nmsec/CC, not Nsec/C*C

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