Mistborn science question

[PapaGeoff]

So at the end of The Lost Metal, with a duralumin spike, wax pushes off the top of a skyscraper and makes it to the ship miles away. It specifically says that the steel beams are bent backwards. This got the engineer in me thinking. How large are steel lines. Stress is equal to force over area and the size of the steel lines affects this greatly. A second question with this is: can a coinshot push off of multiple steel sources right next to each other in order to get a stronger push? 

[Firesong she/her]

23 minutes ago, PapaGeoff said:

So at the end of The Lost Metal, with a duralumin spike, wax pushes off the top of a skyscraper and makes it to the ship miles away. It specifically says that the steel beams are bent backwards. This got the engineer in me thinking. How large are steel lines. Stress is equal to force over area and the size of the steel lines affects this greatly. A second question with this is: can a coinshot push off of multiple steel sources right next to each other in order to get a stronger push? 

I don't think the Steel Lines are directly applying the force in the exact way you are thinking about. As, for example, they aren't actually Physical things. They moreso just mark out the direction that the force is applied, instead of applying the force themselves. 

I don't think multiple metal sources (not just steel, any metal), would help. That would imply the multiplication of force beyond what they pull in from Preservation. As they pull in Investiture from Preservation, and that is converted into energy that it used to push or pull on metal. Thus, at most, you are splitting apart the same amount of force into multiple separate blows.  

Edit: Also, you seem to have posted this topic twice. Please try to avoid that in the future. It is not too big a deal, so don't be alarmed. 

Edited September 27, 2023 by Firesong

[Tamriel Wolfsbaine]

On 9/27/2023 at 1:19 PM, PapaGeoff said:

So at the end of The Lost Metal, with a duralumin spike, wax pushes off the top of a skyscraper and makes it to the ship miles away. It specifically says that the steel beams are bent backwards. This got the engineer in me thinking. How large are steel lines. Stress is equal to force over area and the size of the steel lines affects this greatly. A second question with this is: can a coinshot push off of multiple steel sources right next to each other in order to get a stronger push? 

Exciting to potentially see an engineers thoughts on this. 

On 9/27/2023 at 1:42 PM, Firesong said:

I don't think the Steel Lines are directly applying the force in the exact way you are thinking about. As, for example, they aren't actually Physical things. They moreso just mark out the direction that the force is applied, instead of applying the force themselves. 

I don't think multiple metal sources (not just steel, any metal), would help. That would imply the multiplication of force beyond what they pull in from Preservation. As they pull in Investiture from Preservation, and that is converted into energy that it used to push or pull on metal. Thus, at most, you are splitting apart the same amount of force into multiple separate blows.  

Edit: Also, you seem to have posted this topic twice. Please try to avoid that in the future. It is not too big a deal, so don't be alarmed. 

I have to ask about Vin and the scene with the horses... 

In my mind I always viewed steel as burning per push.  Each different line offered a different push. If you push on more lines you burn more steel and you generate the same force on each line you push regardless of pushing on a bunch of horses or a single coin.  

I really need to reread some mistborn because until reading your post I had never thought of steel as having a limited amount of power split between multiple objects.  As I mentioned the scene where Vin duralumin pushes on the horses makes me want to disagree. 

As well as every scene with multiple coins being used.  If using a handful of coins allows for multiple projectiles that all work wouldn't this theory allow a single coin to be shot at far greater speeds and with far greater force?  

The doors in front of the well of Ascension when Vin duralumin pushes them open. Why would she push on them both if that split the force?  Pushing a single door would double it and be far more efficient right?  

I would be curious if you have specific examples of it working like this as I really don't remember it ever being described as less power when multiple pushes are happening at once.  

@PapaGeoff I imagine the duralumin push combined with his iron allomancy might be what explains it.  I really, after so much effort, don't understand the whole conservation of momentum thing.  In my mind this example is the closest thing to rocketing off there is in the book.  The jump was impossibly long and I would like to make a case saying that it was impossible even for a duralumin steel push unaided by iron feruchemy.  If Wax was far heavier and he pushed it could explain these support beams or whatever bending. If Wax then instantly stored as much weight as possible I feel like conservation of momentum could explain the ability to make that jump as it would have taken far more force to get him airborne in the first place.  Is it that cutting your weight in half would double your speed?  Either way we know steel is only half of his tool kit.  And we know that in order for Vin to break the doors she had to brace herself.  I think those beams could only be bent, even with duralumin, if Wax was bracing himself (without pewter he would surely die) or he was tapping a large amount of weight to push into them with and use the conservation of momentum to get that extra umph to get him to the ship. The jump should not have been possible and Kelsier had already spoken of allomantic steel being garbage over water (even knowing he has no allomancy that just makes sense).  

[Treamayne]

6 hours ago, Tamriel Wolfsbaine said:

I really need to reread some mistborn because until reading your post I had never thought of steel as having a limited amount of power split between multiple objects.  As I mentioned the scene where Vin duralumin pushes on the horses makes me want to disagree. 

As well as every scene with multiple coins being used.  If using a handful of coins allows for multiple projectiles that all work wouldn't this theory allow a single coin to be shot at far greater speeds and with far greater force? 

There is a difference between a normal push/pull and a duralumin one. By definition, a duralumin push or pull must split the force if there are multiple lines being used - because, by definition, a duralumin push/pull uses 100% of the remaining iron or steel which then becomes 100% at one line, 50% each for two lines, etc. Likely, a skilled Allomancer with intent (or savant, depending on difficulty) could split this ratio unevenly (say three lines split 50%, 25%, 25%) but I would guess that without specific Intent, the force distributes evenly.

However, normal pushes are likely as you describe. If a normal push uses, for example (numbers made up for the sake of the example), 5% of your Steel, and a flared push uses 10% - then using a separate push on each of 3 coins would use up 15% of your steel. Again, I would expect that a skilled allomancer can split the force, and that is likely part of how Zan was able to be so exact with his steel when he floated and rotated in the air (dividing that ush to multiple anchors, using two or more to keep steady and one vector to rotate slowly (WoA Ch 17)

Spoiler

Zane hung a few feet away. He’d found a coin—Vin couldn’t fathom how—and was Pushing against it below him. However, he didn’t shoot away. He hovered above the wall top, just a few feet in the air, still in a half tumble from Vin’s kick.

As Vin watched, Zane rotated slowly in the air, hand outstretched beneath him, twisting like a skilled acrobat on a pole. There was a look of intense concentration on his face, and his muscles—all of them, arms, face, chest—were taut. He turned in the air until he was facing her.

Vin watched with awe. It was possible to Push just slightly against a coin, regulating the amount of force with which one was thrown backward. It was incredibly difficult, however—so difficult that even Kelsier had struggled with it. Most of the time, Mistborn simply used short bursts. When Vin fell, for instance, she slowed herself by throwing a coin and Pushing against it briefly—but powerfully—to counteract her momentum.

She’d never seen an Allomancer with as much control as Zane. His ability to push slightly against that coin would be of little use in a fight; it obviously took too much concentration. Yet, there was a grace to it, a beauty to his movements that implied something Vin herself had felt.

Allomancy wasn’t just about fighting and killing. It was about skill and grace. It was something beautiful.

Zane rotated until he was upright, standing in a gentleman’s posture. Then he dropped to the wall walk, his feet slapping quietly against the stones.

Just because Vin only noticed the one anchor doesn't mean he didn't use additional smaller/more distant anchors that his Spiked double-steel let him sense that she wouldn't notice without flaring metals.

6 hours ago, Tamriel Wolfsbaine said:

The doors in front of the well of Ascension when Vin duralumin pushes them open. Why would she push on them both if that split the force?  Pushing a single door would double it and be far more efficient right?

Are you perhaps confusing the Door to the Well with the doors to the storage caverns? The door to the Well was only a single anchor (plus the inlay in the floor), and required an Iron Pull, not a Steel Push. WoA Ch 57:

Spoiler

Everything was as expected. There was nothing…

Vin frowned, stepping to the side. One of the inlays bore a particularly thick line. Too thick, in fact. She frowned, inspecting the line as it—like the others—pointed from her chest directly at the stone wall. This one seemed to be pointing beyond the wall.

What?

She Pulled on it. Nothing happened. So, she Pulled harder, grunting as she was yanked toward the wall. She released the line, glancing about. There were inlays on the floor. Deep ones. Curious, she anchored herself by Pulling on these, then Pulled on the wall again. She thought she felt something budge.

She burned duralumin and Pulled as hard as she could. The explosion of power nearly ripped her apart, but her anchor held, and duralumin-fueled pewter kept her alive. And a section of the wall slid open, stone grinding against stone in the quiet room. Vin gasped, letting go as her metals ran out.

HoA Ch 5:

Spoiler

Elend walked to the center of the small cellar, surveying it as Vin began to check the walls. “I found it,” she said a second later, rapping her fist on a certain portion of the stone block wall. Elend walked forward, joining her. Sure enough, there was a thin slit in the stones, barely visible. Burning steel, Elend could see two faint blue lines pointing to metal plates hidden behind the stone. Two stronger lines pointed behind him, toward a large metal plate set into the wall, affixed very securely with enormous bolts bored into the stone.

“Ready?” Vin asked.

Elend nodded, flaring his iron. They both Pulled on the plate buried in the stone wall, steadying themselves by Pulling back against the plates on the back wall.

 

[Tamriel Wolfsbaine]

20 minutes ago, Treamayne said:

There is a difference between a normal push/pull and a duralumin one. By definition, a duralumin push or pull must split the force if there are multiple lines being used - because, by definition, a duralumin push/pull uses 100% of the remaining iron or steel which then becomes 100% at one line, 50% each for two lines, etc. Likely, a skilled Allomancer with intent (or savant, depending on difficulty) could split this ratio unevenly (say three lines split 50%, 25%, 25%) but I would guess that without specific Intent, the force distributes evenly.

However, normal pushes are likely as you describe. If a normal push uses, for example (numbers made up for the sake of the example), 5% of your Steel, and a flared push uses 10% - then using a separate push on each of 3 coins would use up 15% of your steel. Again, I would expect that a skilled allomancer can split the force, and that is likely part of how Zan was able to be so exact with his steel when he floated and rotated in the air (dividing that ush to multiple anchors, using two or more to keep steady and one vector to rotate slowly (WoA Ch 17)

  Hide contents

Zane hung a few feet away. He’d found a coin—Vin couldn’t fathom how—and was Pushing against it below him. However, he didn’t shoot away. He hovered above the wall top, just a few feet in the air, still in a half tumble from Vin’s kick.

As Vin watched, Zane rotated slowly in the air, hand outstretched beneath him, twisting like a skilled acrobat on a pole. There was a look of intense concentration on his face, and his muscles—all of them, arms, face, chest—were taut. He turned in the air until he was facing her.

Vin watched with awe. It was possible to Push just slightly against a coin, regulating the amount of force with which one was thrown backward. It was incredibly difficult, however—so difficult that even Kelsier had struggled with it. Most of the time, Mistborn simply used short bursts. When Vin fell, for instance, she slowed herself by throwing a coin and Pushing against it briefly—but powerfully—to counteract her momentum.

She’d never seen an Allomancer with as much control as Zane. His ability to push slightly against that coin would be of little use in a fight; it obviously took too much concentration. Yet, there was a grace to it, a beauty to his movements that implied something Vin herself had felt.

Allomancy wasn’t just about fighting and killing. It was about skill and grace. It was something beautiful.

Zane rotated until he was upright, standing in a gentleman’s posture. Then he dropped to the wall walk, his feet slapping quietly against the stones.

Just because Vin only noticed the one anchor doesn't mean he didn't use additional smaller/more distant anchors that his Spiked double-steel let him sense that she wouldn't notice without flaring metals.

Are you perhaps confusing the Door to the Well with the doors to the storage caverns? The door to the Well was only a single anchor (plus the inlay in the floor), and required an Iron Pull, not a Steel Push. WoA Ch 57:

  Hide contents

Everything was as expected. There was nothing…

Vin frowned, stepping to the side. One of the inlays bore a particularly thick line. Too thick, in fact. She frowned, inspecting the line as it—like the others—pointed from her chest directly at the stone wall. This one seemed to be pointing beyond the wall.

What?

 

She Pulled on it. Nothing happened. So, she Pulled harder, grunting as she was yanked toward the wall. She released the line, glancing about. There were inlays on the floor. Deep ones. Curious, she anchored herself by Pulling on these, then Pulled on the wall again. She thought she felt something budge.

She burned duralumin and Pulled as hard as she could. The explosion of power nearly ripped her apart, but her anchor held, and duralumin-fueled pewter kept her alive. And a section of the wall slid open, stone grinding against stone in the quiet room. Vin gasped, letting go as her metals ran out.

HoA Ch 5:

  Hide contents

Elend walked to the center of the small cellar, surveying it as Vin began to check the walls. “I found it,” she said a second later, rapping her fist on a certain portion of the stone block wall. Elend walked forward, joining her. Sure enough, there was a thin slit in the stones, barely visible. Burning steel, Elend could see two faint blue lines pointing to metal plates hidden behind the stone. Two stronger lines pointed behind him, toward a large metal plate set into the wall, affixed very securely with enormous bolts bored into the stone.

“Ready?” Vin asked.

Elend nodded, flaring his iron. They both Pulled on the plate buried in the stone wall, steadying themselves by Pulling back against the plates on the back wall.

 

Oof. It has been a good 12 years since I read Mistborn. Yeah it is the stones. For some reason my mind thought that she braced herself against the stone and pushed with duralumin. But it was iron against multiple anchors I guess. 

Good catch with the duralumin. I think I misunderstood what was being said there. A duralumin push should split the power of the push and that makes sense. Duralumin on a single coin should be far greater than duralumin pushing a bunch of coins.  That does make more sense. 

Who knows how much steel Wax had for that duralumin push anyways. It could have been a ton. I do think that the iron feruchemy still likely played a large role in making that jump but there is a world where he simply had a chunk of steel all being burnt at once.  I still don't think the Steel beams would bend without iron feruchemy in this case as a stronger push with no opposition would simply throw him further faster. 

As for the steel being split between multiple beams. I would like to think that the bigger the metal you are pushing on the more force you can generate.  Perhaps that is limited only to normal steel pushes. 

[Treamayne]

1 hour ago, Tamriel Wolfsbaine said:

Who knows how much steel Wax had for that duralumin push anyways. It could have been a ton. I do think that the iron feruchemy still likely played a large role in making that jump but there is a world where he simply had a chunk of steel all being burnt at once.  I still don't think the Steel beams would bend without iron feruchemy in this case as a stronger push with no opposition would simply throw him further faster. 

Oh, his Feruchemy would definitely be required. Both times we see Vin use an un-anchored steel push (returning to Luthadel's walls at the Battle of Luthadel, and attacking the Inquisitor at the Battle of Vetitan) she was within unaided sight range of her target landing spot - and the Ws were at a range requiring aided sight to even see the ship. Sure, some of that could be made up with more steel, but CoM was very likely required - either to establish a vertical parabola to make the distance, or to increase speed horizontally to make the distance before gravity took over (like long-range bullistics). Especially since he was carrying the weight of both of them through the Push (TLM Ch 69):

Spoiler

Wax downed a vial of metals from his belt, replenishing his steel. That jump had been incredible, with Wayne on his back, a flash of rushing wind and power reminiscent of holding the Bands of Mourning. He had barely made it to the ship after slowing their final approach with Allomancy—eventually landing them near some portholes a few feet below the open deck. He expected to get an earful for making Wayne climb the rest of the way.

1 hour ago, Tamriel Wolfsbaine said:

As for the steel being split between multiple beams. I would like to think that the bigger the metal you are pushing on the more force you can generate.

This is absolutely a thing. WoBs:

Spoiler

Quote

Titan_Arum

If a coinshot were to drop a gold coin of size X or an iron coin of the same size X, would the coin with more mass (the gold coin), under normal circumstances, allow the coinshot to vertically push themselves higher than they could with the coin with less mass (the iron coin)?

Brandon Sanderson

Mass is indeed a factor in anchors.

Quote

Brandon Sanderson

Metal vials. People may wonder why Allomancers use them. Why ingest only small bits of metal, which could run out on you? There are a couple of reasons for this.

First off, you don't want to eat too much metal because, simply put, it's poisonous. Kelsier talks a little bit about this in book one, and it's given token nods from characters throughout the series. I don't do a whole lot with it–dying from metal poisoning isn't the type of extended disease you tend to deal with in a novel that only covers a few months time, like this one.

The second reason for metal vials is more simple. Allomancers with the right powers can Push or Pull on sources of metal–the larger the metal source, the harder the Allomancer can Push on it. So, little flakes of metal make a terrible Anchor, and so if you're caught wearing your vials, you aren't giving much of an advantage to your enemies.

 

 

[Tamriel Wolfsbaine]

11 hours ago, Treamayne said:

Oh, his Feruchemy would definitely be required. Both times we see Vin use an un-anchored steel push (returning to Luthadel's walls at the Battle of Luthadel, and attacking the Inquisitor at the Battle of Vetitan) she was within unaided sight range of her target landing spot - and the Ws were at a range requiring aided sight to even see the ship. Sure, some of that could be made up with more steel, but CoM was very likely required - either to establish a vertical parabola to make the distance, or to increase speed horizontally to make the distance before gravity took over (like long-range bullistics). Especially since he was carrying the weight of both of them through the Push (TLM Ch 69):

  Reveal hidden contents

Wax downed a vial of metals from his belt, replenishing his steel. That jump had been incredible, with Wayne on his back, a flash of rushing wind and power reminiscent of holding the Bands of Mourning. He had barely made it to the ship after slowing their final approach with Allomancy—eventually landing them near some portholes a few feet below the open deck. He expected to get an earful for making Wayne climb the rest of the way.

This is absolutely a thing. WoBs:

  Reveal hidden contents

 

 

This is great thank you for those WoB's. It answers a question I had posed in the cosmere discussion a while back also. So why don't allomancers just use 1-2inch tungsten ball bearings instead of coins? They can generate more of a push on them as the mass would be so much higher and with the way that the allomancer is going to be so much larger it makes sense that a mistborn gearing up for war should just carry some bigger ammo. My personal reasons for using coins instead would be the same reason so many law enforcement agencies moved to the 9mm from other larger caliber weapons. Higher capacity and you dont usually need the bigger gun against squishy targets. Why carry a few larger ball bearings into battle against enemies that wear no armor due to your magic allowing you to manipulate the armor they would wear when you can carry around a far larger amount of ammo that is just as effective against squishy targets anyway? A few hazekillers with wooden shields don't mean much against a mistborn who can choose to leave at any given moment anyway. As far as Wax's time in era 2... why burn steel when you can shoot guns anyway? That is just a different form of conserving energy. Use steel for mobility and let the inexpensive ammunition in your firearms do a lot of the work for you. Less likelihood of running into the "and then his stormlight/steel/pewter ran out" scenarios that are so common in the books. But that WoB does point to a larger, heavier projectile being a better option when facing heavily armored opponents. We just haven't explored a need for bigger ammo on Scadrial yet... guns sort of jumped past it. 

The more I think about it the more I would say Wax got extremely lucky with that jump. I envision steel pushes to be like shooting an arrow out of a bow. The force of the bow being your allomantic power, the weight of the object (or person's being moved) as being the broadhead of your arrow and the anchor you are trying to use being the shaft and spine of the arrow. Most pushes have such a great difference in size and power and a strong enough spine that they work out exactly how they are meant to when they are used. I think the bending of these steel beams is proof of just how unfamilure Wax was with the Duralumin. Not only a sign of how strong the push was, I think it shows that he was not expecting such force and power from the allomancy used. In order to get that effect he really needed to be way heavier via iron than normal plus have an influx of power that he was not expecting. The bending of the beams suggest that some of the energy from the push was wasted. Like shooting an arrow with a massive arrowhead and a weak spine is nearly as bad as dry firing your bow, the anchor almost didnt support him. In archery that comes when both the arrow head is to heavy and the power of the bow is too great for the spine. A heavy arrowhead alone and a heavier bow alone dont usually end with damaged arrows, but both together can lead to catastrophic failure. 

If the Duralumin splits the possible force between beams I would say 1 less beam and they would have surely shattered under that weight, a weight that Wax likely was not unfamiliar with using for jumps in the past. But had he been lighter, while the beams wouldnt have buckled and he could have gotten a better push, would he have had the ability to play with conservation of momentum to make the jump?  

Anyways, I am no engineer nor physicist so I really dont know if this comparison is fair. I do think that archery offers a better explanation for how steel pushes work than guns in my mind but I am open to that being changed. Maybe you could compare it to a really hot load being run through a chamber and barrel that just arent made for it (I fired a really hot .44 mag through my marlin a while back that a buddy had loaded up for me and it about destroyed that pretty lever gun). I definitely like the example used and pointed out by @PapaGeoff and it is a fun thing to look at. We don't see a ton of examples of steel or iron being used and the anchor almost breaking, usually it just does or it doesn't.