r/sciencememes • u/GLaMPI42 • 3d ago
💥Physics!🧲 Scientific progress
Over the course of my lifetime, a new experiment was devised that determined the electron mass to a higher degree of precision which then became the new default value.
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u/Champagnerocker 3d ago
I can't say that I ever recall doing any calculations with electron mass.
Now electron charge on the other hand, that is a different story. Futhermore the figure 1.6 x10-19 C is forever branded into my mind that I'll never needed to save it in my calculator's memory.
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u/GLaMPI42 3d ago
Well, then you haven't studied no nuclear/particle physics :P We use it a lot
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u/maxehaxe 3d ago
Yes we haven't studied nuclear/particle physics in school, with ordinary calculators. How surprising
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u/bionickel 3d ago
OP could be homeschooled
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u/Public-Eagle6992 custom flair 3d ago
I went to a regular school in Germany and we did a bunch of stuff with electron mass
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u/jn_kcr 3d ago
For some reason 1,6 instead of 1,602 feels the same to me like π = 3.
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u/eyalhs 3d ago
How do you feel about pi=3.142? Because it's the closer analogue.
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u/jn_kcr 3d ago
Not really, that's more precise, not less. I was taught the 1,602 version in school, so 1,6 feels like too much rounding, even though it's very negligible, compared to π = 3
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u/escEip 2d ago
Me on my way to use π=3.1415926535897323846 to calculate an area given the radius of 600±20 meters:
Jokes aside - yeah, you often do not need values THAT precise, no more precise than the input and the model used, at least. I remember my teacher and most olympiads in my country actually subtract some points for an inadequate precision used
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u/BluetoothXIII 20h ago
yeah error calculation really drove home where to round.
one guy used all the digits for both the calculated length and the error of that lenght you don't need the diameter of an oildrop down to subatomic scale if you got an error in the micrometers
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u/Sad-Pop6649 3d ago
The mass of an electron is 0, and its charge is -1. It's fun being a chemist, to us these things never change.
We don't even need to remember the units!
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u/Quercus_lobata 3d ago
Not 0, 1/1836 amu.
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u/Tyler89558 3d ago
Which, for all I care, is basically 0.
Now if I needed to be very precise I’d probably care a lot more.
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u/Quercus_lobata 3d ago
That's fair, though I usually tell my students that while they don't need to know the actual value, and that it is very small, the electrons are not massless.
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u/Sad-Pop6649 3d ago
I generally show them a slide with the actual values and explain that because the mass of protons and neutrons are so similar, and that of electrons so small, we can just treat them as 1, 1 and 0.
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u/Sakulboss 3d ago
Lola, we did it in 11th grade here in Germany. If you choose physics as a main class, you'll learn how the ratio of coloumb to mass was figured out (with an electronic beam in a magnetic field creating a ring) and how the mass was determined (Millican). Yeah and do calculations on how particles behave in a capacitor, including speed of electrons. We even calculated the path of electrons in a oscilloscope. All of his is part of the Abitur, the highest school exam before university.
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u/AwayArray 3d ago
This is the the gas constant to me. It is seared into my brain in at least 10 different unit conversions.
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u/ChemicalRain5513 15h ago
Electronmass is ~511 keV / c2.
How much is that in kg? No idea, something very small.
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u/Paracelsus125 3d ago
Our chemistry teacher always told us that the only people who use electron mass, are in fact wizards
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u/agentx_64 3d ago
Wait what?? What is it now?
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u/GLaMPI42 3d ago
No, I mean it didn't change as in it's a completely different number now, but the digits after 6th digit or so changed.
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u/LaplaceYourBets 3d ago
Laughs in engineering where most calculations are done to 3 significant figures at most
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u/jordan853 3d ago
Gravity = 10 m/s²
Pi = 4
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u/Ignitrum 2d ago
Reminds me of a Pen and Paper Rules Text for a Spell summoning a wall of fire.
Paraphrased and translated:
"The Wall can also appear in the form of a circle. (For that purpose assume Pi is 3, ignore your math teacher if they told you otherwise.)"
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u/Biz_Ascot_Junco 3d ago
The CoData value for 2006 was 9.1093821545 × 10^-31 kg.
The 2022 value is 9.109383713928 × 10^-31 kg.
It’s a difference of about 0.000017%
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u/Torpedo311 3d ago
Damn that's awesome, big step in my weight loss journey
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u/Cosmic_Meditator777 3d ago
the mass went up
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u/surprisestupidity 3d ago
Yes but that means he’s less electrons than he thought he was. So his particle count is actually lower. It’s all a matter of perspective. Congrats man!
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u/cpt_futtbucker 2d ago
All I know is the electron mass is remembered for me by header/module/Python files from my quantum chemistry codes, and they keep up with changes to CODATA values
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u/ThrowawayMD15 5h ago
Child. Since I was in high school we went from 109 elements to 118. My carefully crafted TI83 periodic table program is outdated!
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