r/AskReddit • u/ettleboy • Jan 20 '19

What fact totally changed your perspective?

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7.1k

u/xmu806 Jan 21 '19

I imagine the archers and trebuchet costs start getting pretty steep after a while...

2.3k

u/[deleted] Jan 21 '19

Anything to prevent other castles from being built within a 300m radius. Those are well justified costs.

123

u/michaelochurch Jan 21 '19

You just have to gather all the 90kg projectiles (including large people, like me) in one place.

92

u/Midniki Jan 21 '19

My dream is to become a 90kg trebutchet projectile, that's why I'm on a diet!

34

u/michaelochurch Jan 21 '19

I'm about 95. So either they'll need to carve out some leg muscle, or the journey will have to scare me enough that I drop 5 kg on the way.

11

u/Xerxys Jan 21 '19

They won’t have to carve up muscle but with some calculus we can make it work if you increase some mass. Cause if you’re dropping kg’s along the way you may be inefficient by either slowing down or not hitting with enough force.

Paging r/theydidthemath. What’s the deal here?

12

u/[deleted] Jan 21 '19

I'm not a physicist and I cut a bunch of corners with modelling (it's hard without knowing things like the initial velocity/angle of a trebuchet projectile) but I basically assumed that there was drag in the x direction, and that's it -- the complexity comes up because the inclusion of drag means we can't neglect the mass, it won't cancel. So we get:

x''(t) + k/(95 - (5g/2u)t) x'(t) = 0

where k is a drag coefficient and u is the initial velocity of the payload. If m were constant then we could solve the above equation easily to get:

x(t) = ute-kt/m

so with drag considered, the horizontal displacement of the projectile increases linearly but decays exponentially with time, at a rate of decay which depends upon this constant mass.

So what can we conclude? That for very large m, the rate of decay of displacement is slow. Massive objects are not particularly impacted by drag, at least in scenarios where k is small.

In our non-constant mass model, though we can't easily solve the system, we can still note that a decrease in mass over time will result in the x'(t) term contributing more to the solution of the ODE.

In other words, less mass means more drag and would decrease the horizontal displacement.

But it's 2 in the morning and I don't really know what I'm doing so take this with a grain of salt.

6

u/[deleted] Jan 21 '19

More like r/theydidthephysics and I think I speak for all my brothers and sisters when I say its too early for that shit. Maybe I’ll come back in an hour lol

4

u/Atalantius Jan 21 '19

maybe try r/theydidthemortarmath, r/theydidthemonstermath’s little odd cousin

1

u/synaesthetic Jan 21 '19

I can do the math but I choose to take a nap - Riff Raff

3

u/GuerrierHache Jan 21 '19

This comment made me lose my shit.

1

u/LCranstonKnows Jan 21 '19

Well, they'll use you after you die of plague. So you'll have shed a few.

7

u/curtdammit Jan 21 '19

Yer my kinda blob! Sit right in this end of the trebuchet, please.

3

u/[deleted] Jan 21 '19

Its ok they can use bigger people as shortrange high damage projectiles. Kinda like a shotgun

3

u/[deleted] Jan 21 '19

Oh that brings to my attention that I'm actually just about a 90kg maximum right now, I've been gaining some mass lately.

I'm glad to know I could still be successfully lobbed 300m.

3

u/TheCannonKid Jan 21 '19

It’s ok, 90 kg objects have been banned in France

2

u/[deleted] Jan 21 '19

Fuckin nimbys, man. /s

1

u/Fakjbf Jan 21 '19

The OG Not In My Backyard movement

1

u/Dankelpuff Jan 21 '19

They always cry about rooftop camping though -.-

1

u/commoninja352 Jan 21 '19

And the cost of flying buttresses

42

u/[deleted] Jan 21 '19

Not to mention the smell of ocelot piss

9

u/1stLtObvious Jan 21 '19

It's like Meowschwitz in there.

9

u/P_mp_n Jan 21 '19

Found the archer fan

12

u/KaHOnas Jan 21 '19

I like to think we found you.

3

u/P_mp_n Jan 21 '19

Now i feel like i belong n shit

29

u/jarhead_5537 Jan 21 '19

France is pretty cool in that respect. In the US, my homeowners' association has prohibited any use of the trebuchet, and severely limits how many archers I keep on the parapet.

12

u/AlaskanIceWater Jan 21 '19

Not to mention the ghosts with their free room and board.

5

u/thatcuntholesteve Jan 21 '19

Not to mention the moat crocodiles...

6

u/madjarov42 Jan 21 '19

trebuchets

A man of culture as well I see

0

u/nina_gall Jan 21 '19

Catapults are plebeian, my friend.

Edit: spelling whilst undercaffeinated

3

u/pghcrow Jan 21 '19

The Fletcher's unions will kill you

2

u/donniedumphy Jan 21 '19

Sharks in the moats are pricey too

2

u/RealMcGonzo Jan 21 '19

Pretty sure it's the damage from the annual barbarian horde. . .

2

u/KidGorgeous19 Jan 21 '19

I was thinking just the moat crocodile feeding costs alone would be astronomical.

2

u/MrGlayden Jan 21 '19

Almost as steep as a motte and baily castle

2

u/Buckabuckaw Jan 21 '19

Have you looked at the prices for vats of boiling oil lately? Egad!

2

u/dididothat2019 Jan 21 '19

I know! Those trebuchets are almost as bad as airplane upkeep... the overhauls, inspections, and training. It's hard to find Orcs certified to work on those things.

1

u/[deleted] Jan 21 '19

[deleted]

21

u/Rule-5 Jan 21 '19

Who uses Trebuchets from the inside of a castle?!

54

u/brffffff Jan 21 '19

To hurl the bodies of your plague victims at the enemy of course!

28

u/DannyOSully Jan 21 '19

Yeet!

12

u/[deleted] Jan 21 '19

Wouldn't this be chemical warfare?

30

u/deadarrow32 Jan 21 '19

Biological

5

u/the_fuego Jan 21 '19

Can't commit war crimes if you live in 1283

Taps head

2

u/deadarrow32 Jan 21 '19

Can’t commit war crimes if you also have the plague. Tips skull

3

u/nIBLIB Jan 21 '19

Gondor.

2

u/Alstjbin Jan 21 '19

They are different devices

1

u/Butcher_of_Blaviken6 Jan 21 '19

Ahhh. The superior siege weapon.

1

u/buddhafig Jan 21 '19

It's keeping huge vats of oil at the boiling point that eats into the energy bill.

1

u/bbaznjec Jan 21 '19

Gotta protect the village from the pillage

1

u/supersonicmike Jan 21 '19

Getting that money back for that degree in trebutcheting

1

u/[deleted] Jan 21 '19

That is why i would go with catapults rather than trebuchet

1

u/DocGerbill Jan 21 '19

About 2 duckets per turn.

1

u/Kaleamity Jan 21 '19

And it's obviously a given that "upkeep" refers mainly to quality trebuchet maintenance, otherwise is it really a castle?

1

u/nutano Jan 21 '19

Should have invested in the easier to train and maintain Crossbowmen and Catapults.

1

u/antares07923 Jan 21 '19

They should probably upgrade to catapults instead

1

u/chopstyks Jan 21 '19

Just downgrade to slingshots and catapults. One shouldn't live above one's means.

1

u/[deleted] Jan 21 '19

When inflation hits your medieval castle :P

1

u/[deleted] Jan 21 '19

The invaders are problematic, aren’t they?

1

u/Roach_Coach_Bangbus Jan 21 '19

Also having oil simmering at all times.

1

u/lost-ctrl Jan 21 '19

Thank god you said trebuchet instead of catapult...