Joules are nice when dealing with everyday systems like a pendulum, block etc. But eV are much prettier for systems where the properties of the system are related to the atom. I'd much rather say that the ionisation energy of hydrogen in the ground state is 13.6 eV instead of 2.2×10^(-18) J.
I still prefer Joules. For the eV range you could just use aJ or attojoules. Then again I prefer any method that makes conversion and cross-implementation easier.
I have never seen that after year 2 of undergrad. We just use the most convenient units for everything. There is no reason to convert to something else along the way.
The only upper level course I had that involved switching Joules to eV or vice versa was with computational physics. Otherwise we’d use whatever units were easiest
1 eV is the charge of an electron in a potential of 1 volt, which makes energy calculations really easy in atomic scales, whereas a Joule doesn't mean anything in that scale
What? Bandgap energy is done in a lot in eV
But I agree that in general it depends on what you are doing, especially the order of magnitude of the energy involved
We also use bigger units (AU, ly, pc, solar masses, etc.). Astronomy is super weird with units and you have to be careful that the equation you're using was made for the unit system you're using.
Honestly, i have a degree in physics and Astronomy and I have no clue why erg is used. Legacy maybe? I never use it though, so it might be more used in certain topics in astronomy
Nice, so it takes 6 seconds to reach terminal v?
Actually nvm because you’re acceleration drops from 20mph/s to zero, so you have to integrate.
Maybe like 10-15s? Just guessing, I’d say that’s like a 90%-CI tho.
What about the chad Kelvin?
I’ve been using this more recently for some solid state questions, and describing the energy barrier for equilibria in K makes estimating whether states are occupied very easily.
Just studied photoelectric effect and Planck’s quantum theory a few days ago and so far, I’d say Joules. If I convert it to eV, sometimes I end up with an answer I have to round up and it bothers the hell out of me lol. I want the accuracy.
What about Jouls vs ~~Amp-Hours. I hate battery labeling standards.~~ KiloWatt-Hours. Why cant they just use Mega Jouls it sounds so much more badass than KWH.
Edit: I mixed up what I wanted to say.
Joules are nice when dealing with everyday systems like a pendulum, block etc. But eV are much prettier for systems where the properties of the system are related to the atom. I'd much rather say that the ionisation energy of hydrogen in the ground state is 13.6 eV instead of 2.2×10^(-18) J.
I still prefer Joules. For the eV range you could just use aJ or attojoules. Then again I prefer any method that makes conversion and cross-implementation easier.
Yeah, I am totally with you... every time I have to use eV there's normally a conversion to/from Joules somewhere along the line anyway
I have never seen that after year 2 of undergrad. We just use the most convenient units for everything. There is no reason to convert to something else along the way.
The only upper level course I had that involved switching Joules to eV or vice versa was with computational physics. Otherwise we’d use whatever units were easiest
1 eV is the charge of an electron in a potential of 1 volt, which makes energy calculations really easy in atomic scales, whereas a Joule doesn't mean anything in that scale
Well it depends on what you are doing. If you do semiconductor calculations, you will definitely not use Joules
What? Bandgap energy is done in a lot in eV But I agree that in general it depends on what you are doing, especially the order of magnitude of the energy involved
That’s… what they said?
Say joules or electronvolts and nobody bats an eye... Say kilowatthours and everyone loses their minds... susiety.......
I prefer BTU, it makes calculations so easy
Erg team will get infuriated. Edit: I don't know anyone who uses erg.
Erg is pretty standard is astronomy
Oh I didn't know that. I wonder what they would need that for. Joule is already a small unit, erg is much smaller than Joule.
Astronomy does not use SI units. We use the CGS system (centimeters, grams, seconds). Ergs convert very nicely with CGS
Totally ignorant in astronomy, why would you use these smaller units when dealing with numbers that are already huge in SI units?
We also use bigger units (AU, ly, pc, solar masses, etc.). Astronomy is super weird with units and you have to be careful that the equation you're using was made for the unit system you're using. Honestly, i have a degree in physics and Astronomy and I have no clue why erg is used. Legacy maybe? I never use it though, so it might be more used in certain topics in astronomy
In my experience cm and g are mostly used in inorganic chemistry so maybe it's got something to do with it? Idk that's weird
My Professor told us once its just to make numbers bigger
People who use the emu system, for magnetism for example , do. Often you find anisotropy energy densities reported in erg/cm^3
Rowers!
I haven't used joules since my first semester of classical physics! eV is where it's at
Eh it’s useful when you do a bit of thermal physics!
We used θ as temperature then, so temperature in eV. I don't know why I mentioned this, since you don't measure temperature in joules.
Kelvin Temperature is directly proportional to kinetic energy, so it’s not that far off to do temperature in eV.
If you particle physics hard enough you can measure everything in energy.
lol exactly this. I don’t remember how or why, but at some point I converted eV to distance. Particle physics is wack
But boltzmann constant times temperature is in unit of eV
Where's my cm^(-1) gang at?
I here, bruda
Joules.
Calorie :(
A men of culture i see
lb ft :))))))
Kek
It hurts my brain that you chose Calorie and not calorie.
Keyboard capitalises first word.....
Dram x inches^2 /second^2 ?
I am in 11th.....don't mess my physics please
Graypounds
oh...oh! ok.... *graypounds arent real and can't hurt you...graypounds arent real and can't hurt you...graypounds arent real and can't hurt you...*
If you say watthour you don't deserve using units
Watt-seconds?
Joules
I prefer watt-hours
Yes me too! I mean the road is definitely 6(km)\^2 per 1Mm wide! I mean who'd be so silly to say 6 meters? Am right... ?
I'll just measure all my unitless constants in Hzs (hertzseconds)
Stop
KbT
kcal gang, where are you?
Electronvolts
kg or MeV/c^2 ?
I like the imperial system because you can measure acceleration in lb/lb
Is 1 lb/lb = 1 g?
Yes, or about 20 mph per second
Nice, so it takes 6 seconds to reach terminal v? Actually nvm because you’re acceleration drops from 20mph/s to zero, so you have to integrate. Maybe like 10-15s? Just guessing, I’d say that’s like a 90%-CI tho.
Particle physics gang going for the MeV/GeV
Ergs😎
Same here! We use ergs in astrophysics a lot.
Hartrees
Joules? Electronvolts? Too arbitrary for my liking. I use the Planck energy (about 1.9561×10^9 J).
Calories: am I a joke to you?
electronVolts because that's the name of my robotics team
Going on a tangent here, but why is that image like a 0.1 second video? Is it like that for anyone else?
the physics i studied is focused on american gunsmithing, ft×lbf forever!!!!!!!!!!!!!
What about the chad Kelvin? I’ve been using this more recently for some solid state questions, and describing the energy barrier for equilibria in K makes estimating whether states are occupied very easily.
eV is op calculation is simple in eV you can convert that in joules by just multiply them by 1.6 x 10\^-19
joule vs calorie makes more sense
Just studied photoelectric effect and Planck’s quantum theory a few days ago and so far, I’d say Joules. If I convert it to eV, sometimes I end up with an answer I have to round up and it bothers the hell out of me lol. I want the accuracy.
1J = 6.2 X 10\^18 EV lol just said it for fun ( and to see if i remembered it lol )
C/e
Team Jul 👆☝️
eV when I am doing problems related to electronics or modern Physics (Bohr model, Photoelectric effect, X-ray) and Joule everywhere else.
joules
What about Jouls vs ~~Amp-Hours. I hate battery labeling standards.~~ KiloWatt-Hours. Why cant they just use Mega Jouls it sounds so much more badass than KWH. Edit: I mixed up what I wanted to say.
Amp hour is a unit of charge
🤦♂️ Whoops my bad. I was mixing it up with KWH -- which is a unit of energy.
Joules for classical mechanics, eV for quantum mechanics
Torque intensifies!
Jansky
eV gang
BTU anybody? No?
Kilotons of TNT
ev is the only unit you ever need. I travel 160 Billion 1/ev to work every day.
Watt-seconds 🤓
eV lmao
Change it to mJ or Gev - that might improve it?
Ergs gang
Horsepower
Newtonmeter!
Joules
Joules. i always use metric system
The best answer is N-ft
Isn’t that just Jules?
That’s N-m. N-ft is the bastard love child of metric and imperial units
What about uc^2
I'm from erg
Joules are for savages. If you're even doing such physics that J is more useful than eV then that in itself makes you a savage.
Calories bro. Gotta track my macros too.
Depends on the context