# Tag Info

## New answers tagged unit-conversion

1

The SI units for electromagnetism are based on the ampere, which is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 meter apart in vacuum, would produce between these conductors a force equal to $2\times10^{-7}$ newton per meter of length. One coulomb ...

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Coulomb (C) is the derived unit for charge in SI. One coulomb is the amount of charge in one ampere-second. The elementary charge (charge of one proton or (-) electron) is ~1.602E-19 Coulombs. $C = A*s$ The units work out the in the equivalency, which never requires breaking the Coulomb into its base units, as follows: Netwon: amount of force used when ...

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EV stands for exposure value. The equation to convert EV to lux is: $$L = 2.5 \times 2^{EV}$$ Since you're using a Sekonic meter note that Sekonic provide a conversion chart here.

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The first formula is written in the Gaussian unit system, while the second one is in the SI system. In the Gaussian system, the unit of electric charge is $statC =g^{1/2}cm^{3/2}s^{-1}$. So, the Sommefeld parameter in the Gaussian unit system is dimensionless as it would be.

0

$N=CV/m$, hence your solution turns into $\frac{C}{m}$, which doesn't look right (electric field in V/m = force in N / charge in C) I suppose, that answers your question. You can use Wolfram Alpha for unit conversion, for example in your case. And here you'll see how force relates to voltage: ...

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When I wrote a units package, I put degFinterval and degCinterval as units, specifically units that are intended to be squared and multiplied and divided. I put "interval" in the name to make it absolutely clear to users that they should only be multiplying temperature differences (which don't have a fixed origin) rather than raw temperatures (which do). (In ...

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It greatly depends on what you need to do with your temperature. In almost all physics applications, the thermodynamic temperature is the only one that is meaningful. A notable exception is in linear heat flow simulations, where temperature differences only are important (e.g. between a point in the simulated region and the "ambient"). The squared ...

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If you are using an absolute temperature, you should use Kelvin. For instance, when using the Stefan-Boltzmann Law, $$P=A\epsilon\sigma T^4$$ it wouldn't make sense to have units of $^\circ C^4$; only units of $K^4$ physically make sense here. However, if you are using a temperature difference, then both Celsius and Kelvin are equally valid because a ...

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The unit $^\circ\mathrm{C}^2$ does make sense. It represents a difference in temperature squared. You are worried that it is invalid because the origin is shifted. This is not a problem though, because we use $\mathrm{m}^2$ all the time, and there is no natural origin at all for positions.

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