Eheran
@Eheran@lemmy.world
- Comment on As Trump lifts sanctions on West Bank settlers, anti-Palestinian violence flares in the occupied area 7 hours ago:
Those from 6th of January. ALL pardoned.
- Comment on As Trump lifts sanctions on West Bank settlers, anti-Palestinian violence flares in the occupied area 8 hours ago:
Setting free murders etc. seems worse? But oh well, only day 1.
- Comment on Hulu quizzing about the ads played 2 days ago:
Yeah imagine someone shooting a q breast.
- Comment on naughty naughty 2 days ago:
Why on Facebook? :(
- Comment on naughty naughty 2 days ago:
Wait, is that a libgen and scihub combo?
- Comment on Think twice if once isn't working 2 days ago:
Only if the clutch etc. is working correctly. But damaging amounts of power are not going to happen unless that Stihl is really about to fall apart.
- Comment on Photons 1 week ago:
Alright then. But at 0 °F it is not going to melt without your intervention, no matter how sunny it is.
- Comment on Photons 1 week ago:
Yes, while the radiation puts more energy in than the convective etc. cooling removes. So near 0 this is guaranteed, since the temperature difference from ice to ambient is almost 0 while radiation keeps pumping in something like 0.5 W. But who eats ice at freezing temperatures… And outside?
- Comment on Daily inspo 😘 1 week ago:
Ripley is way up there, almost like Arni in predator.
- Comment on Daily inspo 😘 1 week ago:
Didn’t she lose all the time?
- Comment on The surprises found just moving a mattress 1 week ago:
Woooosh?
- Comment on Photons 1 week ago:
It is not direct sunlight that is melting your ice mate. Let’s say the scoop has 10 cm² getting blasted from the sun, that’s 1 Watt of heat under maximum possible conditions (Sun vertically above you, perfectly black ice, etc.). tl;dr: In total from convention 1.8 W and condensation 2.5 W and radiation 0.65 W = 4.95 W -> maximum possible sunlight on earth would only increase this by 20 %, more realistic sunlight something like 10 %.
Actual math: Compare that to ambient temperatures of say, 30 °C, and let’s again say 10 cm² cross section, which translates to a diameter of 3.57 cm, so a sphere with a surface of 40 cm². The heat transfer coefficient under normal conditions is about 15 W/(m²K), so we get: 15 W/(m²K) * 0.004 m² * 30 K = 1.8 W
Additionally, we have latent heat from water (humidity) condensing on the cold surface: Let’s assume a Schmidt number of 0.6, so we get a mass transfer coefficient of: 15 W/(m²K) / [1.2 kg/m³ * 1000 J/(kgK)] * 0.6^(-2/3) = 0.0176 m/s Specific gas constant: 8.314 J/(molK) / 0.018 kg/mol = 462 J/(kgK) So the mass flux (condensation speed) is: 0.0176 m/s * 2000 Pa / [462 J/(kgK) * 273 K] = 0.00038 kg/(m²s)
Given the heat of condensation of 2257 kJ/kg water we thus get: 0.00038 kg/(m²*s) * 2257000 J/kg = 632 W/m²
And thus for our little sphere: 632 W/m² * 0.004 m² = 2.5 W
… Then we also have radiation from the hot surrounding, let’s assume 30 °C again, we get: Q = 5.67E-8 W/(m²*K^4) * 0.004 m² * (303 K^4 - 273 K^4) = 0.65 W (omitting radiation from the sky)
- Comment on Can enough solar pannels decrease the global temps? 1 week ago:
No, quickly as in years. There is no more coal or oil formed today, there are now organisms that can digest every part of organic stuff. There were none back then for example for lignin from wood, which is where we got coal from.
- Comment on Can enough solar pannels decrease the global temps? 1 week ago:
Correct, but not only is it extremely little, this stored energy is also quickly released again after the organism dies.
- Comment on Can enough solar pannels decrease the global temps? 1 week ago:
Just note that the released energy of burning fossils (or nuclear) is orders of magnitude below what the sun does. It really is only the CO2 from coal that does the heating, since it acts like insulation.
- Comment on Which one are you? 2 weeks ago:
How does heat turn things into rubber? The meat I reheat was already cooked? Or am I always too gentle to experience that? I usually do not heat up to boiling hot since I want to eat it and not have to let it cool down first.
Again, your generalization does not make sense. 50 % of a 1000 Watts microwave is different to one with 600 Watts. Heating up a bit of leftover is different to something for multiple persons. Etc. etc.
- Comment on Which one are you? 2 weeks ago:
What do you mean, never? Do you never heat water, coffee, tea, …? Or just larger quantities where more power is no problem even for longer durations? This is not a fundamental thing, the optimum is different not just based on type, amount and distribution of food, additionally things like time constraints or cleaning matter.
- Comment on It insists upon itself 2 weeks ago:
Huh? Was it?
- Comment on True love 2 weeks ago:
Same reason there is no hair surviving on the knees etc., it gets too much physically interaction.
- Comment on Go into debt if you have to 2 weeks ago:
Step 1: Buy LNG tanker Step 2: Step 3: Profit
- Comment on Anon's lacking pissing habits 2 weeks ago:
I hope this was a joke.
- Comment on Why is it that clasped hands tends to be the norm for praying? 🙏 2 weeks ago:
How did people like that? Crazy.
- Comment on One what? 2 weeks ago:
Mate, I just saw a video, it is clearly fireworks.
- Comment on One what? 2 weeks ago:
Is there a video? No link here.
- Comment on New year, new me 2 weeks ago:
How could anyone create such a picture with metadata?
In any case, now anyone looking roughly like that = Danny Devito? Why does he own that look?
People have copied works from others… Always. All of our society and tech is based on that.
- Comment on F.B.I. Says It Found Largest Cache of Homemade Explosives in Its History at Va. Farm 3 weeks ago:
Largest cache… a backpack…? So they never found more because they failed to stop them after getting a tip 2 months prior to the attack?
- Comment on Graphic Design Is My Passion 3 weeks ago:
But how?
- Comment on Why is daisychaining multiple extension cords considered unsafe, even if only done to the length of a standard cable? 3 weeks ago:
So many people here talk about the thickness needed of else it heats up. That is simply wrong. The heat is the same per length and is dissipated the same way with twice the length aka the temperature is the same*. The issue is that the short circuit current could drop below the value needed to actually pop the breaker, allowing for a ton of heat to be generated where it shouldn’t be. The same way a light bulb glows bright hot but does not trip the breaker etc., now just imagine the cable to be the glowing part.
*There is another issue if you do not lay them out, that the heat has nowhere to go. Causing coiled wires to have a far lower rating compared to when they are fully extended.
- Comment on Why is daisychaining multiple extension cords considered unsafe, even if only done to the length of a standard cable? 3 weeks ago:
When the breaker trips then the fundamental issue is unlikely to be present. But to be able to push enough current to cause it to break the connection needs to have a sufficiently low resistance. If that gets too high it will never break, even if you short the cables. And that will result in a fire, because the protection does not work anymore. That is the dangerous part.
- Comment on ACA 4 weeks ago:
Hahaha literally my reaction!