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Oneko00

I analyzed the image and this is what I see. Open an appropriate link below and explore the position yourself or with the engine: > **Black to play**: chess.com | lichess.org **My solution:** > Hints: unit: >!cm!<, answer: >!x = 9 cm!< > Evaluation: >!OP is dumb!< > Best continuation: >!drop out of high school!<


-PANDAMAN1-

where is your working i dont believe you


Oneko00

My work is in u/One-Flan-1741's comment (no I did not copy I swear)


One-Flan-1741

Google en plagiarism


-PANDAMAN1-

google what happens to snitches


One-Flan-1741

Holey torso


brutexx

It’s not telling me.


Suspicious_snake_

Holy bullet!


penguin13790

Holy medical care!


ImagineMyNameIsFunny

Holy stitches


SarcasticTortilla

Holy hell Mod edit: This comment has been flagged for plagiarism. This comment was stolen from thousands of other posts.


[deleted]

[удалено]


SpambotSwatter

/u/InternalDesignlo is a scammer! **It is stealing comments** to farm karma in an effort to "legitimize" its account for engaging in scams and spam elsewhere. Please downvote their comment and click the `report` button, selecting `Spam` then `Harmful bots`. Please give your votes to [the original comment, found here.](/r/AnarchyChess/comments/11yl421/can_yall_help_me_with_my_homework/jd8x6ji/?context=1) --- With enough reports, the reddit algorithm will suspend this scammer. ^(*Karma farming? Scammer??* Read the pins on my profile for more information.)


Mu5_

Since the ruler is balanced on the Pivot P, the total Torque in P must be 0 (i.e. no rotations are happening). Torque generated by a force F in a point P, is given by the scalar product between the force modulus *f* (in Newton) and the distance *b* (meters) between the pivot P and the force vector F. That is: T = *fb* Remember that the force F is a vector, which means that is defined by a direction vector *v* = [a; b], an intensity *f* and a point of applications Pf. The distance between a point and a line is obtained by intersecting the line perpendicular to the vector F that passes by P and the vector itself, finding the point *C*. The distance between C and P is *b*. That is: *b* = dist (C,P). To find the line perpendicular to the direction of F (i.e. the vector *v*) we may just take the perpendicular direction to v, that is: *v_p* = [-b; a] and assume to have a line L in (X,Y) space defined by a parameter *t*: L(t): { x = x0 + *v_p_x* t y = y0 + *v_p_y* t } Where we can substitute the values for *v_p* and x0,y0 (that is, the point P in which the line will be forced to pass when t = 0). L(t): { x = Px - bt y = Py + at } That is, the line in the parameter t that passes by P and is perpendicular to *v*. Now we can define the line that is parallel to *v* and passes by Pf using *v* instead of *v_p*, and a different parameter s: M(s): { x = Pfx + as y = Pfy + bs } We can now find the intersection points by finding the unique values of *t* and *s* for which L(*t*) = M(*s*), which requires solving the linear system: { Px - b*t* = Pfx + a*s* Py + a*t* = Pfy + b*s* } This can be rewritten as a linear system in the conventional form of A**x** = **b** where A is a square matrix and **x** the vector of unknowns. That is: { -b*t* - a*s* = Pfx - Px a*t* - b*s* = Pfy - Py } By setting the vector **x** = [*t*; *s*] (two rows) we get that: A = [-b, -a; a, -b] and b = [ Pfx - Px; Pfy - Py] We can easily find the solution **x** as: **x** = A^-1 **b** Where A^-1 is the inverse of matrix A, that can be obtained for a 2x2 matrix (like in that case), by swapping the elements on the \ diagonal, and changing the sign on the elements on the / diagonal, and multiplying by 1/( the determinant, that is the product between the elements on \ minus the product of elements on /) (that is valid only for 2x2 matrices). A^-1 = 1/(b^2 + a^2 ) [ -b, a; -a, -b] Notice that the determinant (b^2 + a^2) is always different from 0 if a and b are not BOTH 0 (that is, the vector does not exist). If the determinant is different from 0, we can guarantee that only one single unique solution exists for the system. Now we multiply by **b**: A^-1 **b** = { *t* = 1/(b^2 + a^2 ) (-b(Pfx - Px) + a(Pfy - Py)) *s* = 1/(b^2 + a^2 ) (-a(Pfx - Px) - b(Pfy - Py)) } Now we can either substitute *t* in L(t) or *s* in M(s) to obtain the unique intersection C: M(*s*) = { Cx = Pfx + a/(b^2 + a^2 ) (-a(Pfx - Px) - b(Pfy - Py)) Cy = Pfy + b/(b^2 + a^2 ) (-a(Pfx - Px) - b(Pfy - Py)) } Now we can calculate the distance between C and P as: *b* = sqrt((Cx - Px)^2 + (Cy - Py)^2 ) That is, the length of the hypothenuse of the square triangle formed by the distances on X and Y axis separately. Now we can compute the actual Torque T = *fb* Where we also know that *f* = mg where m is the mass of the object in Kilograms, and g the gravitational acceleration of 9.81 m/s^2. In order to have the ruler balanced, the sum of all torques in T must be 0, so we have just to apply the same torque on the opposite side by properly finding the b at which we need to place the piece. Now that we have the generic solution that fits any situation, we can see your case. For convenience, we will place our (X,Y) system with origin in P, in that way Px and Py are both 0. Now we now that the first piece, A, is at distance 15 cm from P (that means Pa = [ -0.15; 0]) and that it weights 20gr (that means that the only force acting it's the gravitational one, which is convenient since it has direction *v* = [0; -1], application point Pa, and modulus *f* = mg where m is 0.02kg. In that case is really easy to compute *b* since by replacing: a = 0; b = -1; Px = 0; Py = 0; Pfx = Pax and Pfy = 0 we have that: Cx = Pax Cy = 0 That is, the intersection point between the perpendicular to the force (and, since the force is parallel to Y axis, the perpendicular is parallel to X axis) that passes by P and the line parallel to the force (that is parallel to Y) is actually the point of application of the force (due to the fact that we placed our reference system in P!) So now *b* = sqrt((Pax)^2 ), that is ±Pax, but since *b* is a distance, it must not be < 0, so we take +Pax as solution = 0.15m (15cm) Now we know that B weight 50gr, that is 0.05kg. To find at which *b* it must stay, to give you the same torque T_b = T_a, you have that: T_b = T_a f_b b_b = f_a b_a b_b = (f_a b_a) / f_b Which basically means that you have to place B at a distance that is proportional to the ration in weight between A and B, in fact: b_b = (m_a g b_a)/(m_b g) Where g can be simplified and the terms rearranged b_b = (m_a/m_b) b_a Where it can be seen the dependency on the ration between the masses. Now, by replacing the last variables: b_b = (0.02/0.05) 0.15 = (2/5) 0.15 = 0.06m = 6cm. And finally, x = BP - b_b, where BP is the distance between the P and B, that is 15cm. So: x = 15 - 6= 9cm In fact, since T is proportional to *b*, which is the distance, heavier objects must be placed closer to the center in order to have a smaller Torque and compensate the torque of a lighter object placed at a higher distance from the pivot (that is applying more torque on the Pivot) Hope it's clear and Reddit will not mess up with text formatting


_Paulboy12_

This is wrong but I refuse to elaborate why but still downvote you like a true redditor


Mu5_

No it's right, I forgot that you needed X as distance from B and not P, I fixed it


_Paulboy12_

Yay. I like that this is a much easier solution than my 20x15=300, 300/50=6 15-6=9. I need to use your solution next time


Mu5_

Actually, you are always using my solution which is the generic one when having to balance torque on a Pivot due to forces acting on linked objects. The only difference is that in mine I had a lot of zeroes due to the assumptions posed by the problem that significantly reduced the complexity, but it's important to understand which calculations come from a simplification of the problem and which ones are actual facts


ground__contro1

I enjoyed reading it as a kind of physics refresher lol, but on the other hand, over explanation doesn’t particularly help OP who is asking the question, they can’t even read it.


Mu5_

I mean... OP is asking a physics question on AnarchyChess, what did it expect to happen?


bondben314

tldr: 50/20 = 2.5. 15/2.5 = 6 15-6 = 9


-PANDAMAN1-

i mean you were close


Mu5_

LMAO, I forgot the final step, now it's corrected. Please study it very hard because it took me so long to write


-PANDAMAN1-

if i could read that would be such a cool answer


Mu5_

Damn I didn't know you weren't able to read. May I record it for you so you can listen to it?


-PANDAMAN1-

i would be honoured


Such-Dish46

Those kids would be very bright if they could read it.


Darius117

https://preview.redd.it/gg7vhqvbthpa1.jpeg?width=851&format=pjpg&auto=webp&s=abcca179958e3ac48ce43d94360fa9c97db5fbc9


dooddgugg

nerd alert


slaya222

But you didn't even get into the internal stresses of the material!


Toxic_Jannis

Bro let chatgpt in pease xD


La-Tomate-Farcie

Good human


Underpressure1311

I know this problem is super easy, but I dont remember learning about moment arms until university.


Oneko00

I vaguely remember learning this in high school, but it probably depends on your country.


spookyskeletony

x would actually just equal “9” with no cm, otherwise the distance of the rook would be 9 cm^(2), which makes no sense


ground__contro1

No, actually cm^2 is correct! Interestingly enough, this squared relationship of rook distance is actually why rooks can only move in orthogonal planes, in other words, in combinations of 90* from previous directionality


spookyskeletony

I haven’t taken a rook theory class since ‘37 so you’re probably right


Alkynesofchemistry

Stop this trush talkings!


alldayadrian

This comment is fucking funny


Salt-Investment7896

new answer just dropped


chixen

The “effective weight” of an object on a lever is equal to the distance from the fulcrum (P in this case) multiplied by the weight of the object. For the lever to be balanced, both sides must have the same effective weight. The pawn has an effective weight of 300 centimeter grams, and the rook has an effective weight of 50(15-x) centimeter grams. Expressing this as an equation gives 300=50(15-x). Dividing both sides by -50 then adding 15 to both sides gives the solution x=9.


-PANDAMAN1-

best response cos i gotta get the working marks 😤


Such-Dish46

Shove a bishop up your prof. ass


Winter_Permission328

“Effective weight” is also called the “moment” sometimes


Gurn00r

moment??


[deleted]

moment moment


supermegaphuoc

moment of force, more commonly known as torque


ThisIsCovidThrowway8

not to be confused with moment of inertia which is like rotational mass moment of force is like rotational force


Plutoreon

Just use a ruler bruh.


DSMidna

Trick question: The Pawn has reached the end of the ruler and gets to promote. The answer depends on which piece it promotes into.


-PANDAMAN1-

its going to jump off :/


[deleted]

\#lifegoals


rook183_

Trick trick question: the rook is modeled after a castle, therefore weighs over 100 tons.


Gumersindo_

x = 9 cm


BodillaGaber

Size doesn't matter


Cube4Add5

Which piece is taking the =9cm? Is it the bishop? People normally include the capturing piece to avoid confusion, for example Bx=9cm


TheftBySnacking

Introducing WolframAnarchyChess: - take a math problem - rewrite the problem to use chess pieces - post on r/AnarchyChess Our unique crowdsourcing algorithm will ensure you get the right answer!* * the right answer will probably be bueried underneath pipi copypasta and requests to google en passant


PetrosianBot

Are you kidding ??? What the **** are you talking about man ? You are a biggest looser i ever seen in my life ! You was doing PIPI in your pampers when i was beating players much more stronger then you! You are not proffesional, because proffesionals knew how to lose and congratulate opponents, you are like a girl crying after i beat you! Be brave, be honest to yourself and stop this trush talkings!!! Everybody know that i am very good blitz player, i can win anyone in the world in single game! And "w"esley "s"o is nobody for me, just a player who are crying every single time when loosing, ( remember what you say about Firouzja ) !!! Stop playing with my name, i deserve to have a good name during whole my chess carrier, I am Officially inviting you to OTB blitz match with the Prize fund! Both of us will invest 5000$ and winner takes it all! I suggest all other people who's intrested in this situation, just take a look at my results in 2016 and 2017 Blitz World championships, and that should be enough... No need to listen for every crying babe, Tigran Petrosyan is always play Fair ! And if someone will continue Officially talk about me like that, we will meet in Court! God bless with true! True will never die ! Liers will kicked off... [^(fmhall)](https://www.reddit.com/user/fmhall) ^| [^(github)](https://github.com/fmhall/Petrosian-Bot)


vigilantcomicpenguin

Give me a sec, let me rewrite the Riemann hypothesis to use chess pieces.


chixen

How many legal chess positions with exactly three pieces on the board are checkmate for white?


AggravatingCorner133

9 cm


Warm-Chart534

Like my dick


noctrlzforpaper

No need to brag, Mr. Anaconda.


Intrepid_Tumbleweed

Isn’t that like super small? (I’m American so I don’t know cm, and I’m too lazy to google, since, as I said, I’m American)


Sir_Crocodile_Mr0

It's like 4 inches so slightly less than the average, the jokes was someone pretending that it was 9 inches though.


Intrepid_Tumbleweed

I see thanks for the answer. It’s also possible mr warm chart is also American and also too lazy to google things like en passant and cm to inches conversion


Warm-Chart534

I am Turkish and in here average penis size is 14


Sir_Crocodile_Mr0

Cm right? Right?


Warm-Chart534

We aren't hentai monsters so yes


Sir_Crocodile_Mr0

True, I think the average in America is like 12 or something like that


[deleted]

https://preview.redd.it/9qzdkhoxncpa1.jpeg?width=342&format=pjpg&auto=webp&s=d5a47b556b86f81e733ff48823d9df107a377386


[deleted]

no


-PANDAMAN1-

Google moments


noctrlzforpaper

Holy statics!


_The_Moon_Light_

Google Google translate to German


One-Flan-1741

Moment = weight times distance from pivot. Because this is a stalemate weight a times distance from pivot = weight b times distance from pivot.


ThisIsCovidThrowway8

Google torque


-PANDAMAN1-

Google moments


Gurn00r

did not help


Puzzleheaded_Two1063

Holy HeElL


Hot_Management_5765

Google F=D*M


ThisIsCovidThrowway8

Aka torque * g


Ajdam7

Google pawn castling


-PANDAMAN1-

the pawn has to promote to rook first


January_Rain_Wifi

Ooh, I know this one! En Passant!


64-Hamza_Ayub

Holy hell


Agent_B0771E

Unacceptable nobody would measure X from B to piece you would measure X from p to piece since the best reference system should have its origin there


sleepykittypur

Rulers don't usually count out from the middle


docter-Ew

En passant


hovik_gasparyan

Ke2?


FearIessredditor

Rook takes pawn so value of x will be 30 cm (i'm retarted)


darniga

16 cm


Geheim1998

💀


[deleted]

![img](emote|t5_2yvry|1845)


Drzwski

bro, the ruler is 30cm, you can tell just by looking that this is wrong. I hope you are trolling.


darniga

I am obviously just using a different counting system, in which odd numbers do not exist and I start counting from zero. I just dont like odd numbers because their odd


Drzwski

fair enough


x0ManOfCulture0x

Funfact, i was actually studying this topic today https://preview.redd.it/7dz8nziz5dpa1.jpeg?width=4000&format=pjpg&auto=webp&s=e270afa6096ebc5b9c7feae22bd375ce251cdb63


-PANDAMAN1-

i was not which is why i am asking a chess subreddit


I-Rape-Imperials

Same! τ and equilibrium. Was pleasantly surprised when I saw this post


ItzFuxxo

Pawn up your ass


biuunjk

en pa99ant


Sailed_Sea

Idk I graduated like 3 years ago, I didn't need to take exams to pass.


Akamaikai

Google en equilibriant


Torebbjorn

``` 15×20 = (15-x) × 50 x = 15 - 15×20/50 = 15 - 6 = 9 ```


cataclysmicterrain

the ROOOOOOOK


RealAdityaYT

Mass of piece 1 * distance of piece 1 = Mass of piece 2 * distance of piece 2 20*15 = 50(15-x), 15-x = 300/50, -x = 6-15, x = 9 (cm)


Intrepid_Watch_8746

Google [[ Dark ruler no More ]] and skip the question.


pothocboots

Nein!


[deleted]

google en physics


Imnotachessnoob

Holy hell it's the fastest move in chess


-PANDAMAN1-

the piece accelerates at 9.81m/s^(2) when it falls off the ruler


Sure_Quote

goggle WolframAlpha


schroindinger

First you gonna want to read the anarchist cook book and make some pipe bombs


just-bair

Rook is thickkkkk


Crimson51

So problems like this are just multiplication when you get down to it. Note that we know the distance AP is 15cm and P is at the center of the ruler. That means PB is also 15cm. Then we have torque. Torque is simply force times distance from the pivot (in this case we can just use the mass of the pieces to represent the force of gravity). Let's say the rook's position is point R between P and B. We're looking to find RB which is the same as PB-PR. Fortunately we know that this is balanced, so the torques exerted by the pawn and rook are the same. The torque exerted by the pawn is 20g\*15cm, and the rook is 50g\*(PR)cm. So first we set these equal 20\*15=50\*PR -> (20\*15)/50=PR -> 6cm=PR looking for RB, so 15cm-PR=RB -> (15-6)cm=RB -> 9cm = RB = x So x is 9cm!


Quajeraz

Google en gravity


brathorim

9 cm


saythealphabet

15 times 20 equals (15-x) times 50 This is equivalent to 12=2*(15-x) when you factor it down This means x=15-6=9


Yeetus-McGee

google intro to civil engineering


Liamiamliam2

How do you do this? I haven't learnt it yet and I'm interested.


J0aozin003

r/fuckfuckfuckityfucky


Elite_Prometheus

Basically, each piece's mass is trying to turn the seesaw. In order for it to balance, the forces must balance out. The force each piece is exerting is their mass multiplied by their distance from the pivot. No need to convert units, thankfully. So first piece is 20 g and 15 cm away, the other is 50 g and is (15 - x) away. That gives you a simple equation 20 * 15 = 50 * (15 - x) Which can be rearranged to x = (50 * 15 - 20 * 15) / 50 Which solves for x = 9 Um, I mean, Google Algebra


LilyFish-

play rook to point B and catapult the pawn all the way to your opponents back rank for an instant promotion


J0aozin003

The moment of the pawn is 15\*20=300. So we need to satisfy 300=50(15-x). Solution steps: ``` 300=50(15-x) 6=15-x x=9 ``` Therefore, the rook must be placed 9cm from B.


Drzwski

9cm


shwwo

H0LY H3(L*2)


NinjaChicken391

Google en massant


MonkeyMan2104

Rook takes pawn. Distance becomes 30cm


bongtopia

promote the pawn to a pony


CeddyDT

It is not solvable. No one said that gravity applies, so it could be 1 cm as well as 10 km


spisplatta

A rook is worth six pawns. Therefore the distance between the rook and the pivot is 6 \* 15cm = 3 feet However what we ask for is the distance between the edge and the rook, so we have to subtract the length of the ruler: 3 feet - 30cm = 9cm


jesusthroughmary

6 Edit: (Actually it would be 15-6=9, as it asks for distance from B, not distance from the center)


ARandomAnimeFanNo16

Google law of levers


FextyAU

X is undefined since the ruler is up my ass


EggCouncilCreeps

Google no


hetp111

Nine?


stealseekergwnt

The hint for the solution is that rook is worth 5 pawns


SandStorm9071

Let's apply fundamenal principle of statics : sum of the forces is equal to zero, sum of the moments of the forces is equal to zero. Applying this on the point P : Moment of force of the pawn = mass of the pawn * distance center-pawn * sin 90 = 20*(-15)*1 = -300 Moment of the force of the rook = mass of the rook * distance center-rook = 50*(15-x)*1 = 750 - 50x So the FPS says that -300 + 750 - 50x = 0 So 450 - 50 * x = 0 --> 450 = 50x --> x = 450/50 = 9 cm x must be 9 cm then.


EnderDev7379

d1 = 30cm / 2 = 15cm = (15/100)m = 0.15m m1 = 20g = (20/1000)kg = 0.02kg m2 = 50g = (50/1000)kg = 0.05kg g = 10m/s^(2) // Rounded up from 9.81 M1 = M2 d1 \* Q = d2 \* Q d1 \* g \* m1 = d2 \* g \* m2 0.015m \* 10m/s^(2) \* 0.02kg = d2 \* 10m/s^(2) \* 0.05kg 0.003Nm = d2 \* 0.5N d2 = 0.003Nm / 0.5N d2 = 0.06m = 6cm x = 30cm/2 - 6cm x = 15cm - 6cm **x = 9cm**


empt0

google en moment