Why is ketchup so hard to pour? - George Zaidan

Prevodilac: Maja Berović Lektor: Ivana Korom

French fries are delicious.

Pomfrit je ukusan.

French fries with ketchup are a little slice of heaven.

Pomfrit sa kečapom je pravi mali raj.

The problem is it's basically impossible

Problem je što je u suštini nemoguće

to pour the exactly right amount.

sipati tačno odgovarajuću količinu.

We're so used to pouring ketchup that we don't realize

Toliko smo navikli da sipamo kečap

how weird its behavior is.

da ni ne primećujemo koliko je čudno njegovo ponašanje.

Imagine a ketchup bottle filled with a straight up solid like steel.

Zamislite bocu za kečap napunjenu čvrstom supstancom,

jakom poput čelika.

No amount of shaking would ever get the steel out.

Nikakvim treskanjem

nije moguće izvući čelik.

Now imagine that same bottle full of a liquid like water.

Zamislite sada tu istu bocu

napunjenu tečnošću poput vode.

That would pour like a dream.

To bi se izlilo kao san.

Ketchup, though, can't seem to make up its mind.

Ipak, čini se da kečap ne zna šta činiti.

Is it is a solid? Or a liquid?

Da li je on čvrsta supstanca? Ili tečnost?

The answer is, it depends.

Odgovor je, pa - zavisi.

The world's most common fluids like water, oils and alcohols

Većina uobičajenih tečnosti poput vode, ulja i alkohola,

respond to force linearly.

reaguje na silu linearno.

If you push on them twice as hard, they move twice as fast.

Ako ih pritisnete dvostruko jače, one se kreću dvostruko brže.

Sir Isaac Newton, of apple fame, first proposed this relationship,

Ser Isak Njutn, poznat po anegdoti s jabukom, prvi je uočio ovu relaciju,

and so those fluids are called Newtonian fluids.

pa se stoga takve tečnosti nazivaju njutnovskim tečnostima.

Ketchup, though, is part of a merry band of linear rule breakers

Kečap, pak, pripada veseloj družini narušitelja ovog linearnog zakona

called Non-Newtonian fluids.

koje se nazivaju ne-njutonskim tečnostima.

Mayonnaise, toothpaste, blood, paint, peanut butter

Majonez, pasta za zube, krv, boja, puter od kikirikija i mnoge druge tečnosti

and lots of other fluids respond to force non-linearly.

reaguju na silu nelinearno.

That is, their apparent thickness changes

Drugim rečima, njihova prividna debljina menja se zavisnosno od toga

depending on how hard you push, or how long, or how fast.

koliko jako pritišćete, koliko dugo ili koliko brzo.

And ketchup is actually Non-Newtonian in two different ways.

A kečap je zapravo ne-njutonovski

na dva različita načina.

Way number one: the harder you push, the thinner ketchup seems to get.

Prvi način: što jače pritisnete,

čini se da će kečap izaći tanji.

Below a certain pushing force,

Do određene sile pritiska kečap se, u suštini, ponaša kao čvrsta supstanca.

ketchup basically behaves like a solid.

But once you pass that breaking point,

Ali, jednom kada prevaziđete tu kritičnu tačku,

it switches gears and becomes a thousand times thinner than it was before.

kečap menja ponašanje

i postaje hiljadu puta tanji nego što je pre bio.

Sound familiar right?

Zvuči poznato, zar ne?

Way number two: if you push with a force below the threshold force

Drugi način: ako pritisnete silom manjom od granične,

eventually, the ketchup will start to flow.

kečap će najzad početi da teče.

In this case, time, not force, is the key to releasing ketchup

U ovom slučaju, vreme,

a ne sila, je ključ za oslobađanje kečapa iz staklenog zatvora.

from its glassy prison.

Alright, so, why does ketchup act all weird?

U redu, dakle, zašto se kečap ponaša tako čudno?

Well, it's made from tomatoes, pulverized, smashed, thrashed,

Pa, pravi se od paradajza,

usitnjenog, smrvljenog, drobljenog,

utterly destroyed tomatoes.

potpuno uništenog paradajza.

See these tiny particles?

Vidite ove sitne čestice?

This is what remains of tomatoes cells

To je ono što ostaje od ćelija paradajza

after they go through the ketchup treatment.

nakon što prođu kroz tretman kečapa.

And the liquid around those particles?

A tečnosti oko tih čestica?

That's mostly water and some vinegar, sugar, and spices.

To je pretežno voda i nešto sirćeta, šećera i začina.

When ketchup is just sitting around,

Kad kečap samo sedi okolo,

the tomato particles are evenly and randomly distributed.

čestice paradajza su ravnomerno i nasumično raspoređene.

Now, let's say you apply a weak force very quickly.

Sada, recimo da vrlo brzo primenite slabu silu.

The particles bump into each other,

Čestice naleću jedna na drugu, ali ne mogu da se mimoiđu,

but can't get out of each other's way,

so the ketchup doesn't flow.

pa time ni kečap ne teče.

Now, let's say you apply a strong force very quickly.

Pretpostavimo da brzo primenite jaku silu.

That extra force is enough to squish the tomato particles,

Ta dodatna sila je dovoljna da iscedi čestice paradajza,

so maybe instead of little spheres,

pa se možda umesto malih sfera ispretumbaju u male elipse, i bum!

they get smushed into little ellipses, and boom!

Now you have enough space for one group of particles

Sada imate dovoljno prostora

to get passed others and the ketchup flows.

da jedna grupa čestica prođe kraj drugih,

pa kečap teče.

Now let's say you apply a very weak force but for a very long time.

Recimo sada da primenjujete vrlo slabu silu,

ali dovoljno dug vremenski period.

Turns out, we're not exactly sure what happens in this scenario.

Čini se da i nismo baš sigurni šta se dešava u ovom scenariju.

One possibility is that the tomato particles near the walls of the container

Jedna od mogućnosti je da se čestice paradajza

blizu zidova posude

polako pomeraju ka sredini,

slowly get bumped towards the middle,

leaving the soup they were dissolved in,

ostavljajući supu u kojoj su rastvoreni, a koja je u osnovi voda, blizu ivica.

which remember is basically water,

near the edges.

That water serves as a lubricant betwen the glass bottle

Ta voda služi kao mazivo

između staklene boce i središnjeg čepa kečapa

and the center plug of ketchup,

and so the ketchup flows.

i tako kečap teče.

Another possibility is that the particles slowly rearrange themselves

Druga mogućnost je

da se čestice polako međusobno preuređuju u puno malih grupa

into lots of small groups, which then flow past each other.

koje se zatim međusobno mimoilaze.

Scientists who study fluid flows are still actively researching

Naučnici koji proučavaju protok tečnosti i dalje aktivno istražuju

how ketchup and its merry friends work.

na kom principu kečap i njegovi veseli prijatelji funkcionišu.

Ketchup basically gets thinner the harder you push,

Kečap u suštini postaje tanji što jače pritiskate,

but other substances, like oobleck or some natural peanut butters,

ali druge supstance, poput Ubleka, ili nekih prirodnih putera od kikirikija,

actually get thicker the harder you push.

zapravo postaju deblje što jače pritiskate.

Others can climb up rotating rods,

Druge se mogu uspeti uz rotirajuće štapove

or continue to pour themselves out of a beeker,

ili nastaviti da se izlivaju iz čaše,

once you get them started.

nakon što ste ih počeli izlivati.

From a physics perspective, though,

Sa aspekta fizike,

ketchup is one of the more complicated mixtures out there.

kečap predstavlja jednu od komplikovanijih smeša.

And as if that weren't enough, the balance of ingredients

I kao da to nije dovoljno,

balans sastojaka i prisustvo prirodnih zgušnjivača

and the presence of natural thickeners like xanthan gum,

poput ksantanske gume, koji se takođe nalazi

which is also found in many fruit drinks and milkshakes,

u mnogim voćnim napicima i mlečnim šejkovima,

can mean that two different ketchups

može značiti da se dva različita kečapa mogu potpuno drugačije ponašati.

can behave completely differently.

But most will show two telltale properties:

Ali većina će pokazati dva karakteristična svojstva:

sudden thinning at a threshold force,

naglo stanjivanje pri graničnoj sili

and more gradual thinning after a small force

i postepenije stanjivanje

nakon što se mala sila primenjuje duži vremenski period.

is applied for a long time.

And that means you could get ketchup out of the bottle in two ways:

A to znači da kečap možete istisnuti iz boce

na dva načina:

either give it a series of long, slow languid shakes

ili mu date niz dugih, sporih laganih treskanja,

making sure you don't ever stop applying force,

pazeći da nikad ne prestanete da primenjujete silu,

or you could hit the bottle once very, very hard.

ili možete jednom snažno udariti bocu.

What the real pros do is keep the lid on,

Ono što pravi profesionalci rade jeste da drže poklopac,

give the bottle a few short, sharp shakes

daju boci nekoliko kratkih, oštrih protresanja,

to wake up all those tomato particles,

kako bi probudili sve one čestice paradajza,

and then take the lid off

a zatim skinu poklopac

and do a nice controlled pour onto their heavenly fries.

i dobro kontrolisano sipaju kečap na svoj nebeski pomfrit.