Forging Weapons from Neutron Stars - Sixty Symbols
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- Опубліковано 7 жов 2024
- Dr Becky Smethurst explores a scene from the film Avengers: Infinity War - and Stefan-Boltzmann constant.
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I hope there is a future marvel comic where they just "happen" to talk about the specific heat capacity and melting point of Uru.
he will certainly block a lazor with his hammer at some time and then they might give information about if it is at risk
have some contrived plot where iron man and wolverine fall into flowing molten vibranium and when they float or sink or whatever, Captain America rattles off the densities, specific heat capacities, phase transition boundaries and Young's moduli of all the weird comic book materials.
But exists expecific informations about lightsabers!
I think you ignored the latent heat of fusion of the metal. There is a time during the melt where the phase change sucks up all the energy you would put into changing the temperature, and this definitely increases the amount of energy required. The heat of fusion for tungsten is 35.4kJ/mol, which means you have 3.695kJ added to your energy term to actually melt the metal. I guess compared to the 8000kJ of heating the metal it's not that much, but still.
It should be the area of the opening. It's there for that specific reason, they don't just throw it into the star's orbit.
Jacobe 1701 they have to calculate for the entire star because that’s how it is in the movie. Entire energy of the star concentrated into one beam directed towards the metal.
Latent heat of fusion isn't going to get you from a nanosecond to a minute.
It doesn't matter... do it right or don't do it at all :)
Perhaps that’s where the “magic” part of the metal comes in; an extremely high heat of fusion?
Would it be possible to assume the metal takes 1 minute to heat and assume some properties of the star and work out the metal's melting point from those?
but what would you estimate the heat capacity as?
I honestly though that was the direction they were going to take, sadly they did anything but. The thing that's the most "special" is the metal used, hence why they need a neutron star to melt it. If it was a normal tungsten-like metal, why would they go through the whole trouble using a neutron star? That's a complete waste. The whole reason they needed that crazy setup is because it's a special metal that can't be worked any other way.
Yeah, that's the way I would have liked it, too. We know the time, we know the properties of a neutron star (roughly) so we could find out the metal properties. Probably couldn't calculate the melting point though, only the product of melting point and heat capacity but that's better than nothing.
You would have to work backwards just like they did, which is what I find odd that they chose to try to find out the temperature of the sun instead of the melting point of the Uru
Elias Aronsson Yea that would be an issue. Maybe they could estimate it from the properties of other particularly strong metals?
Why not treat the heat capacity and melting point as an unknown, and try to figure it out based on the other stuff?
Marino Šimić dude, I know. Nevertheless, it would be cool to know what the product of the two is. Maybe listen to some theorizing about "maybe the melting point isn't actually that high and the heat capacity is 10^9" and what that would imply, say, for the hammer at room temperature. The energy would be enormous. Or, think about how long it took to cool down and see what the melting point is from that, or... There's at least 2 more videos they could pull from this and I really wanna know more about weird Marvel universe pseudo-physics
Given:
t = 60. s
m = 19 kg
A = 0.50 m² (1 m² seems too high)
σ = 5.67 × 10⁻⁸ W m⁻² K⁻⁴
T₀ = 6.0 × 10⁵ K (temperature of neutron star)
We find that the metal receives tT₀⁴σA/m = 1.2 × 10¹⁶ J/kg. Some of that energy will heat the metal from its initial temperature to its melting point, some of it will go into melting the metal, and some of it will then continue to heat the molten metal afterwards (but that last part might be considered negligible). Without knowing at least three out of the four unknowns (specific heat capacity of solid metal, melting point, heat of fusion, and specific heat capacity of liquid metal), we can't really figure out much more than that. But to be clear, about 50 megatons of TNT equivalent (roughly equivalent to the largest nuclear explosion in history) has gone into that 19 kg hammer.
The temperature/age of the neutron star is equally unknown so it's no more or less valid
The temperature of a neutron star is at least known to within an order of magnitude.
Because they wanted to know the time to hold the door open.
Wait a second. Aren't you missing the energy required for the phase change? Ice doesn't just melt the moment it hits 0C and water doesn't just boil when it hits 100C. It takes a lot more energy to melt the substance once you raise its temp to the melting point.
I think that the latent heat of fusion for tungsten is negligible compared to the energy required to melt it, on the order of 0.05% of the total amount. It can be safely ignored.
As the heat capacity of Uru seems to be the most unknown factor here, I'm disappointed that 600,000K for the temperature of the neutron star and 1 minute for t hasn't been used to calculate it
I'd go with the cooler neutron star thing. I can imagine most neutron stars having formed more than 46 million years ago.
If they had a metal with that much specific heat capacity, they'd make engines out of it! And not some pointless useless weapon.
If my calculations are right (using ∆T=(25000-25) C), the heat capacity of the material would be around 9,2x10¹¹ J/kgK (didnt check the units tho, but the number should be about right).
I think you ignored that the neutron star shines in all directions and is not exactly where the metal is.
So the Power it sheds off is:
P=I*4pi*r(NS)²
So the Intensity at the position of the metal is only:
I(metal)=P/(4pi*d²)=I*(r(NS)/d)² with d the distance between the metal and the neutron star
and then you can use that P(metal)=A*I(metal) with A=1m²
It then probably takes much longer as r~km
and probably d~10⁵ km or something
With the same values you would actually get minutes
This is exactlywhat i though. Not all the heat of the star goes to the metal. Only a small opening of few meters in a km square neutron star.
Also, you'd have to orbit at an huge velocity that would rise as you got closer to increase the radiant flux density and so reduce the melting time.
Comics produce comic book interlects.
In the movie they have a sort of Dyson sphere with a hole in it to focus all the energy in a ray.
The problem remains the same you need to put a thing of a given area at a given distance to receive X amount of luminance, what you do with it after that doesn't matter assuming your collection and transmission systems are perfectly efficient, which they can't be obviously so you have even more losses to calculate therefore more energy to collect.
I haven't seen the movie, but I assume that the neutron star light was being lensed onto the target, otherwise everything would be melting other than just the target.
A big enough lens lets you empulate having the target be an inch from the star.
I love how dr becky is most happy about being able to tell the age of a NS.
Since the Stormbreaker and the Mjolnir are used to control lightning, we must assume uru has a much higher melting point than the temperature of a lightning bolt. Otherwise after a couple of lightning bolts the hammer might melt. So it's melting point must be more towards 50000K rather than 4000K
or that it has a very high heat of fusion, you can take a blowtorch to ice, but it won't melt it, because you need to overcome that latent heat of fusion to get the ice to change from a solid at 0C to a liquid at 0C
Because of the Faraday Effect, wouldn't that just be an issue with the outer surface of the hammer?
😝😝😝😝
This presumes that the lightning is transferring energy to it. We might instead assume that it's some kind of super-advanced superconductive material that near-perfectly channels the energy into the wielder, who in this case is an individual with an inherent ability to be unharmed by and redirect that energy. It would heat up only very slightly due to its near-perfectly conductive nature.
@@Abigail-hu5wf you may have just proved that uru is a superconductor lol im not a marvel fan, but could any other effects of this material be explained by it being a superconductor? Does it ever levitate? Lol
@@Allan_aka_RocKITEman No, because the issue is actually with the plasma that the lightning bolt is, not the electric current flowing through it, as you may already know the blue "lightning" we see is actually a nitrogen/oxygen plasma created by the extremely large potential difference
It took even less than a nanosecond for Becky to melt my heart^^
LOL
For a second, I read that as 'Bucky'. Which I would've concurred with.
@@theblackwidower I too thought the same.
Actually the melting point of the Uru metal should be higher than 25000K. Thor use it very often to strike lightning bolt or to get it by those with hit, so i think the neutron star had to be a little younger. ;D
Comics and overanalyzing things, 2 of my favorite things
Ok, let me explain this to you. First of all, it's not a normal neutron star, this is a semi-neutron star slowly collapsing, they are extremely rear. As you can see from the surface that is not neutrons... So, the device channels extreme electromagnetic radiation and particle radiation onto a godly raw material, with godly properties. The essential property is that it can absorb huge amounts of energy without vaporizing. This process will add energy to the hammer and also mass, sort of an opposite nuclear explosion. The amazing thing is that this metal will store most of the energy as dark matter/energy. This can be controlled by gods giving the hammer it's immense power. Let me know if you have any questions.
If they are extremely rear, how much front are they? Also, why would you be able to recognise neutrons? Maybe you should share your glorious insight of the crust of a neutron star.
Trying to think of something smart, witty, scientific, prophetic to write here..... but really just here for Dr Becky, she’s awesome.
She is amazing, and brings a lot of extra information that is so interesting to hear. I so hope she thinks it is fun and enjoyable so we will see more from her in the future!
You could have just said "OMG, Fit!"
@@GetawayFilms pls no
You also need some energy to turn 3700K solid tungsten into 3700K liquid tungsten.
Fellow D&D players, did you know that Ioun Stones, like the original D&D magic system, come from Jack Vance's _Dying_ _Earth_ stories? In one of the stories we find out how an Ioun Stone is created. It involves ridiculously powerful mages/techs flying to a neutron star, using their magic/tech to survive getting close to it and *carving* *off* a piece of it, and then treating the chunk with various eldritch processes in order to make it stable and to enchant it. Pretty wild.
High intelligence is often indicated by the ability to get complex ideas across to in an apparently simple way. This individual possesses a highly advanced intelligence - as obviously shown in this video. Also possesses the most bewitching eyes that I have yet come across. Fascinating!
Very nice, but I have several comments:
- you assume that all the energy of the star is focused in that beam of light and then directed on the metal. Why not only take a beam like a fraction of the area of the star?
- also, giving the size of the star in the movie, it must be quite far (even a city-sized star would be several kilometers away to look that small. This would decrease the fraction of the area needed, and that I mentioned before.
- finally, neutron stars emit very high magnetics fields. Could we not assume that the metal is fused with induction-heating?
I particularily like the induction idea, for several reasons:
- such intense magnetic fields are specific to neutron stars (whereas heat is common to all stars, and it would be more powerfull to use an active star than a dying star).
- that neutron star looks like to be inside a cage. One might imagine that it is a faraday-cage, and opening it would allow a little of magnetic flux to escape.
Also, regarding the hammer, 19 kg is quite light! For a lump of tungsten to weight that much, it would be only a cube of 10x10x10 cm. If it was steel, it would be like 10x10x20 cm, which would much more ressemble the Mjölnir (another idea might be to consider that tha tungsten hammer is hollow). So I guess that Uru has a high heat-capacity but a low density (something more like steel) and very high strengt (like titanium, maybe).
Otherwise, it’s very fun to see that other people find different ways to explain this sort of stuff from the movies.
Given that we could still openly see most of the star radiating light away in the movie (star wouldn't be visible if literally all the light/heat energy was being channeled away into that beam), it's safe to say not ALL of the energy was actually focused into that beam, just some percentage of it. So I agree with you.
You also have to keep in mind that the heat has to diffuse into the metal, which will not have happend in a few nano seconds. For this you would then also have to estimate the thermal conductivity of the metal.
I have yet to see the film, but if they were melting the metal to form a weapon, they were casting a weapon, not forging one...
Thomas Carrel
lol exactly what I was thinking.......
Perhaps the Nidavellir forge usually forges weapons. But let's be honest, it's difficult to forge a hammer/hammer-axe, so for those special ones, they cast them, but they still need the heat of the forge to do it.
She's a physicist, not a smith. A lot of people confuse the terms, and in this case the difference is literally meaningless.
Can we nominate Becky for most adorable astrophysicist
Yes you can, but then there may be other opinnions about the matter, so you have to reiterate your nomination with a reason for the nomination that stands the rigorous review that follows reasonably intact.
@@Paltse She's unbearably cute
No.
I think there's another effect you need to account for - gravitational red-shifting; which is quite considerable for a neutron star, from its surface to some sensible distance from it (so that you're not getting spaghettified by tidal gravity!).
This will reduce by quite a bit, the power being delivered to the metal.
Fred
Hold on a minute. Thor summons Thunder, which is the percusive force of lightning. Lightning is supposedly thousands of times hotter than our sun. Why does Thor need The Neutron Star again? He should be able to melt Uru with his lightning.
This is absolutely brilliant.
Why didn’t you use the assumed temp of the star and the time for melt to then work out the properties of the metal?
The metal Uru is the unknown in this situation. It's touted as a divine metal after all. It would be far more interesting to take the known values for the properties of a neutron star and the time taken to melt the metal and work out the "divine" properties of Uru from there. I mean, if Uru was at all comparable to tungsten as purported in this video then using a neutron star to power the forge would be a ridiculous amount of overkill.
I haven't heard a word about the distance to the star. Isn't this a variable as well?
Wonderful and fun thanks Dr. Becky 😁
What about the energy required to actually melt the metal after it's been heated to its melting point?
actually, you can assume that temperature of melting of metal must be very high as it is known to stand very high temperatures like in dozens of lightning bolts surrounding it, as we see it happen in the movie.
most of the solid are known to have constant heat capacity(as per as i know) so that is sorted.
such smart guess works can be done.
"So meta." Love it. Awesome video.
Wait, so your calculations say that at 8,700K the neutron star would be able to melt something with a melting point of 25,000K in a minute? Correct me if I'm wrong but isn't it normally impossible to use black body radiation to heat something to a greater heat than the heat of the source of the radiation?
Fun topic. Just as a side note. Doctor, you forget about energy for phase transition from solid to liquid. It's not a negligible number. For "magic" material it could be ludicrously big and it can "justify" necessity for a star to be used. :)
Shockingly thorough ;-)
wait you put the melting temperature to be that of a lightning bolt?
so when Thor makes a lightning bolt, the weapon is gonna melt in his hands?
I love how the iPad Marvel screenshot has Sixty Symbols, MinutePhysics ........and BuzzFeed..... ffs.
kiffe22
Probably based on what the artist would see when they watched UA-cam.
and Veritasium on the bottom, I think.
Maybe they like "Worth It" eats?
Oh, how amazing Becky is...
I literally loved this video. I am physics PhD student and I was preparing exercice about Pikachu and Thunderbolt move. This is exactly how the process looked. Finding some strange sources, reversing all the computations to make something, that doesn't look ridiculous :)
How to harness the energy of the star?
That's the easy part, isn't it?
Just use mirrors.
Basically make a Nicoll Dyson beam.
Didn't he play Merlin in the movie EXCALIBUR?
😊😊😊😊
Forging typically refers to the process of heating and hammering/beating metal into shape, it does not require melting temperatures. Casting is the process of heating to melting point or beyond, then pouring into a mold.
1) Isn't A the area of the neutron star being exposed, not the area of the metal, because it's being focused down onto the metal?
2) You also need to include the enthalpy of fusion into the equation, since the metal does melt.
You are so right, I was thinking the same thing. The equation contains a major flaw... And since the complete video is about that one equation...yeah...I'm sorry sixty symbols...
Dr Smethurst for most underrated Sixty Symbols host!
The metal with the highest melting point is Hf-N-C, which melts at 4400K. Since this material doesn't have a specific name and since the metal in the movie obviously isn't a single element, I'd say it's a more logical choice. It wouldn't surprise me if this is less dense than tungsten.
Either way, it's all just for fun. No point in nit-picking about such minor details, I just thought this one was interesting to point out.
Hf-N-C isn't a metal, but this still doesn't matter since Uru is a ficticious form of matter that could have an enourmous heat capacity and latent heat of fusion, that might just be the reason they need a minute in the movie.
Also, both Stormbreaker and Mjolnir modify their mass whenever someone (who isn't Thor/Odin/Vision) attempts to lift them, obviously bending the laws of physics quite a bit.
Props for knowing about Hf-N-C instead of saying the standard Ta-Hf-C (Tantalum Hafnium Carbide), and yes as stated it is indeed much less dense than Tungsten. Also:
1.Hf-N-C is not a metal, it's a ceramic. Ceramic engineers are really picky about this.
2. More often than not, you cannot and definitely should not melt a ceramic. This has to do with the micro-structure it forms as it cools, becoming more like glass than a crystalline ceramic. In short, there is a reason why ceramics are sintered (powder packed and fused), rather than melted, as they have exceptionally high melting points and have better properties when sintered. Tantalum nitride (TaN), which is the closest compound I can relate to, actually decomposes into Tantalum metal and nitrogen gas instead of melting. I don't know for sure if Hf-N-C decomposes or melts, but the point is that you should not try to melt the stuff.
If I were to make an educated suggestion for what Thor's hammer is made of, I would say Iridium, with a IrB2 coating diffused onto it for durability. "Real rare star stuff", extremely high melting point, tied for highest density, and exceptional mechanical properties. It is also quite inert, so it can be cast without too much oxidization, not that any sane person would melt and cast Iridium.
EDIT: Iridium is also radioactive, which they mention in the first Thor movie.
The Hf-N-C material mentioned is still purely theoretical, isn't it?
Wouldn't Iridium oxidising not be an issue in space (or are they doing all this on an oxygen rich planet?) :)
sidewaysfcs0718 Well, I've been meaning to ask... What if the definition of time is different? I mean it's just nature to assume a minute is a minute, but in a fictional world - a minute is like what they define it to be. So, could it be that they actually heated it for a lot longer but that's their standard minute. I wondered about this when I first saw it actually...
The Uru is melted in a container that is being heated by the neutron star, the metal itself isn't heated directly by the star, but indirectly. The time required is not just to melt the solid ingots of Uru, but to also raise its temperature to a point where it can be cleanly poured into a mould. In the movie the Dwarf throws the mould on the ground and breaks it up, showing that the axe pieces have already solidified and is rapidly cooling down shown by the lack of a bright light radiating from the metal. The Uru doesn't seem to hold heat that well and requires a significant amount of energy to manipulate. Incredibly strong and durable material that is also brittle (see ragnarok).
Math always forgets how impractical the movie world is.
applause, applause,, I always could value math equations much easier when it is in a problem like which you did here,,, Just learning math as math with out relationship to something almost real and I had always done poorly,,, Thank you Dr. Becky
favorite video ever
Love the video, really enjoyed it. Great! But not much stuff floating around space at room temperature, I thought?
I like the mention of the super material. Tungsten is the closest we're going to get in real life, but lets make one up to take us all the way! That's what's so much fun about science fiction. When you encounter plotholes or problems in the story, you can (if you're clever and careful with your story-telling) create ways in which the sci-fi science can solve those problems. If it's pulled off well, it enriches the story. If it's pulled off badly, it's mcguffin.
Love you Dr Becky!
That Sixty Symbols reference is great.
Liked her explanations, and obviously the font. We need to see more of her.
I thought about Sixty Symbols a lot during that scene
Kunal Shrivastava me too
You must be straight as a pole. I was thinking about dem biceps 💪.
DekuStickGamer lol
Three things you need to consider in the equation:
1) the distance from the star, the equation you presented assumes that the metal and the star are attached
2) temperature of the space is 2.7 K not 300 K
3) the amount of heat that is radiated back to space
That's it. I'm quitting my career and going to Nottingham Uni to learn whatever it is Dr Smethurst teaches.
There are some variables that weren't accounted for. Firstly, the distance between the forge and the neutron star. The further away you are from a radiation source, the less energy you will get.
The second variable that wasn't accounted for was the size of the aperture through which the radiation went. The smaller the aperture, the less radiation will get through. You have to take both of those variables into consideration to get more complete results.
Brilliant vid, cheers.
If neutron stars cool off in timescale of millions of years, then isn't it possible that universe is full of neutron stars that we can't observe because they don't emit enough light? Couldn't those millions(?) of neutron stars contribute to the amount of dark matter?
The main property of a neutron star is that it is made of neutrons. The mass is so big that the degeneracy pressure is surmounted and protons and electrons fuse. This gravitational pressure alone would be enough to heat the metal, even ignoring any blackbody radiation.
The question though would be: What would happen to the "neutronized" metal hammer, once it will be removed from the neutron star and exist in normal gravitational surroundings? Would it become metal again? What element?
What a wonderfully nerdy video. I love this so much.
But wouldn't you have to account for the specific latent heat of melting to find out the total amount of energy required?
The moment Dr Smethurst said "46million years", I immediately thought, "Whoa, that's totally plausible."
It seems like a really bad assumption to assume Uru has the same melting point of Tungsten. Tungsten can be melted with furnaces on Earth, so there's no point in building a forge around a star. I imagine the reason the star forge is even needed in the first place was because that's the only way to get the extreme temperatures needed to melt the Uru.
I didn't follow a word... I'm so in love with Dr. Becky!.....
Considering huge magnetic fields normally generated by neutron stars I wonder if metal being place anytime near would melt even faster from induced currents. That would be an interesting estimate to make as well.
Two problems. First, it took a minute. That’s canon now. You should be making assumptions about the neutron star (somewhat known) and calculating the properties of Uru (totally unknown). None of this means anything because Thor didn’t have a tungsten hammer. The second problem I have is that not all the neutron star energy was captured, only what made it through the grate. Even the fact that you can see the Star means that a lot of energy was radiated into space and not captured. This is a very sloppy video.
Mary Jane Watson teaching us the physics of the Marvel universe? How meta!
The Stefan-Boltzmann law also needs an emissivity and a solid angle. You've assumed that the metal is completely black and that the weapon is seeing the neutron star in all directions.
Yea, as we saw in the movie how the star was still visible to us even during the process, it's clear that beam focusing device was still only focusing some percentage of the star's total light/heat energy, otherwise the star would have been invisible during the forging/beam focusing. So yea, there's no way that beam contained all the emitted light/energy in all directions that star was putting out, just from sheer virtue of the fact that is stayed visible to us, so it must still be emitting some waste excess not included in that beam which is hitting our eyes as visible light.
Nice idea for a video. But I think the most important thing to calculate should be the properties of the metal. Those properties are the thing we don't know.
Lets assume uru can contain energy and release it on its wearers will we can calculate the total energy inside the axe.
Makes much more sense to me.
The power of the weapon comes from the stored energy of a neutronstar.
I thought I would add that what's really discussed is melting of metal. Forging is an entirely different process and I assume that with a perky neutron star you could forge like nobody's business, *if* you can keep the metal just below it's 'plastic' flow state. Manufacturing is also about process in addition to the science.
A neutron star has far better ways of releasing energy than by thermal radiation. So, this calculation is at least incomplete. I missed gravity also. That is a bit of a problem near a neutron star among other problems.
I live how the neutron Star in the video is lumpy with mountains and valleys. Wouldn't it be incredibly spherical?
It would be very smooth yes, with the highest irregularities around 5mm or so. They are not spherical though, since especially young neutron stars typically rotate pretty fast (up to around 700 times per second has been observed, the theoretical maximum before they break apart is around 1500/s), they can be quite elongated ellipsoids due to centrifugal forces.
blahfasel2000 right, I should have known that ^^
didn't see it, but already liked.
are we supposed to not all have a crush on Dr. Becky Smethurs after these videos?.......
Tungsten, I though Thor's Hammer was made from a fragment of a Neutron star, why its so heavy, mind blowing stuff Dr. Smethurtst.
well, we can estimate the melting point form the heat glow of the metal. In this case, it glows orange/yellow, so it's probably well under 1000K. That means raw uru has insane specific heat of melting. It is also important to point out, that it does not give away all that energy when it solidifies. That means the end product has different crystalline structure than the original ingot. It also obviously has different melting point, because Mjolnir can withstand lightning.
Uru could just have a ridiculously high heat of fusion and reflectivity at every wavelength except the hard UV emitted by Neutron stars so that heating it up to temperature by any other means is very inefficient and it basically takes the heat of a neutron star to get it melted even though it is at it's melting temperature, just like water at 0C has more heat energy in it than ice at 0C despite the fact they're the same temperature, Uru could have a multiple megajoule per mole heat of fusion.
Wow! 60 Symbols is in Marvel -- You're famous!
Just some thoughts... Because neutron stars spin extremely rapidly and have some of the most intense gravitational and magnetic fields, besides emitting blackbody photons, they also fling out relativistic ions, which would be a significant heat load in the vicinity of the star.
Nice video! Fun to be able to make some realistic assumptions and calculate for something within the fictional domain of Marvel Universe but it also approximates what it might take to really do something like this, we may discover something new :)
This is wrong. It is completely disregarding the distance from the surface of the neutron star, not to mention the energy required to melt something is more than just bringing it to the melting temperature.
have you seen the movie? the entire star is surrounded by a mirror shell that reflects all the light back into it and there is a small aperture, about 3-5m^2 through which a (unexplanedly) collimated beam containing all the star's radiation comes out, so all the stars light hits the forge where the metal is melted, but you're right about them not taking into account the latent heat of fusion for the metal, which is why water is warmer than the same temperature ice, and the reflectivity/emissivity of the metal which controls how quickly it absorbs that radiation, but you could say that the walls of the forge are adiabatic.
I like this video but please use only one background while showing the equations. I think it is really annoying to see the background changing all the time
Wonderful.
Unless I’m mistaken, you need to consider the heat of fusion (energy per mass for a phase transition solid/liquid) as well as the heat capacity here... that could be another place where more energy could be needed to melt the magic uru metal stuff...
Error:
You didn't take into a count energy, needed to melt the metal (you only counted energy, needed to het the metal up to it's melting point).
Also, in the video it is shown, that metal is being melted in some sort of space structure, wich should also be heated by a neutron star, so you could get maximum possible (number of photons)*(their avg. E)/(time*area), recived (absorbed and reflected) by this structure and/or some focusing device if such exists, wich is consistant with it/them not melting and use them to get j* of a neutron star.
it seems like it would be better to start with the fact that it takes a minute then you can figure out the C dt necessary, making asumptions with the melting point or the heat capacity will tell you the other
Here's a though - many neutron starts have polar jets. Perhaps that was what was being referenced here? When I think beam of energy from a neutron star, that's the first thing that comes to mind. I believe they are caused by material falling on the neutron star, which would cover "awakening" the neutron star
Are you sure they're using the neutron star to melt metal, or are they actually extracting a very small amount of neutronium with some sort of powerful magnetic siphon?
... which then is then embedded in the metal, sort of how forging steel binds carbon and iron?
What chemical element are neutron stars made of? Are they a single neutron, or a great many neutrons?
If a Neutron star were a single neutron (and thus hydrogen) and the neutron star was 10 km in diameter, how far away would the electron be?
Damn, i love Becky x'D shes like the most loveable nerd :P
Honestly I’m in love with every single one of the women I’ve seen in Brady’s videos. They remind me of some of the girls I went to school with and make me think that I should be trying to date smarter girls than I have been recently.
Regarding the area in j* (=E/A/t): Don't we need to take the distance to the star into consideration?
A 1m^2 near the star will get more heat radiation (due to a larger angle) than a m^2 far away.
I would even guess that the area would be the area of the star and we would need to use angles to figure out the percantages that hits the weapon forge
Thought Math is done from the wrong direction ,Main objective would be what Type of Metal need 1 minute to melt with 600,000 K temperature .We are more interested about the special metal not the neutron star
neutron star temp is also highly variable
Wouldn't it have been much more fun to assume the properties of the neutron star are about average and then pretend to derive the properties of the metal?
What about the energy it requires to actually melt the metal after it is heated to its melting point. If I'm not mistaken, additional energy is required for a material to change states.
First time I've not watched the whole of one of these vids.
Mind blown. I now have more questions than before I started watching this video:
1) Does the distance from the heat source not factor in the equation somehow? For example as the proportion of the area covered by the surface we want to heat to the entire heat output of the star (i.e. the surface of the sphere at the given distance).
2) Your equation only calculates the energy to head the metal to the melting point. But then you need _additional_ energy to change the phase from solid to liquid.
3) The spaceship has a much larger area than the weapon and is, presumably, not made from Uru. How do you make sure it does not melt long before the weapon does?
4) Why does it have to be a _neutron_ star? We are not using any special properties of the neutrons, we are only using it as a black body heat source. 8000K is well within a ballpark of a normal star.
Nice back of the envelope calc, but shouldn't you use a distance to the forge?
I was thinking, if you want to cool down a neutron star, just throw some water on it, but then I got to thinking, the star has such a high gravity, would the star actually heat up if we through water on it (or anything at all)?
Such a treasure is Dr Becky
What you could also do is figure out the properties of Uru by using the temperature of your neutron star and the one minute melting time . It would end up with crazy melting points or tremendous mass . I’ll calculate that later .