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electron volts: eV
Posted: Mon Mar 30, 2026 9:30 am
by MadAxeMurderer
As of this week I finally understand the point of electron volts.
Same scale as an atto joule. Didn't understand why they didn't just use aJ instead of eV
Now I do.
Same reason cosmologists live a light speed of 1. 1 lightyear/year
It all started with a joke:
Why did the quantum mechanic smoke?
Re: electron volts: eV
Posted: Mon Mar 30, 2026 10:55 am
by Franklan
MadAxeMurderer wrote: ↑Mon Mar 30, 2026 9:30 am
Why did the quantum mechanic smoke?
To make light rays visible?
Re: electron volts: eV
Posted: Mon Mar 30, 2026 10:29 pm
by alison
MadAxeMurderer wrote: ↑Mon Mar 30, 2026 9:30 am
As of this week I finally understand the point of electron volts.
Same scale as an atto joule. Didn't understand why they didn't just use aJ instead of eV
Now I do.
Same reason cosmologists live a light speed of 1. 1 lightyear/year
Same reason we use Watt-hrs, assuredly otherwise a completely stupid unit. The unit is that is most annoying is the SI's adoption of candela, which serves only display makers. That's in contrast to Kelvin, gram, centimeter and ampere, all of which are physically motivated.
The best article I've read about units in years is "Temperature as Joules per Bit":
https://pubs.aip.org/aapt/ajp/article/9 ... es-per-bit It's a quick read for those interested in this topic.
-- Alison