How many papers can you produce a pot of pasta?

For the pasta, the food that we can't be familiar with us weekdays should not only appear on the table in the eyes of physicists. It has a very unique physical properties. It is a pity not to study in the laboratory.

Humans finally fold the pasta into two paragraphs!

Big physicist Ferman once broke a few pasta, but unexpectedly found that the pasta would be folded into three or more sections, and never broke into two sections.

He brought more pasta, pinched the two ends of the past, and bent until the break. He tried many times, and he couldn't break the pasta into two sections. He wrote this discovery into his diary, and for decades, this phenomenon has not been explained well.

Ferman's confusion: How to break one pasta into two sections? | Reference Information [10]

Until 2005, the solution of the problem finally appeared. Basile Audoly and S´ebastien Neukirch, two physicists in France, studied the theoretical interpretation of the phenomenon of cutting and multi -festivals.

Applying pressure at both ends of the past, it will break at the largest position in the middle. Because of inertia, the pasta after the break will be bent in the opposite direction until the pen is restored. The curved state changes in a very short period of time, which will stimulate a strong vibration wave in the mind, which will further break the noodles into more festivals.

This process is known as the Fraction Cascade (Fraction Cascade, the meaning of the English word is a "broken waterfall", which describes the break like a waterfall under the action of vibration waves). The study of the pasta made two physicists win the 2006 Funny Nobel Prize in Physics.

The broken process after the intimidation of high -speed camera shooting | Reference materials [2]

After knowing that the principle of two sections cannot be broken, can it be based on this basis, can the intention really break into two paragraphs?

Wait until 2018, Ronald Heisser and Vishal Patil, two graduate students from the University of Cornell and MIT, discovered the way to break the intention into two paragraphs: Twist and "Quench" To.

Instruments specially designed for the norm breaking | Reference materials [3]

Two graduate students designed a special instrument -the two clips of the two clips of the instrument. On one end, the pasta can be reversed to a certain angle by rotating.

They recorded the broken process after the intimidation of the pasta at a speed of 1 million frames per second. Finally, it was found that the pasta would only break into two segments after turning more than 250 ° at the critical angle.

After the large angle reversed, the pasta was broken into two stages

(The picture above shows the experimental record, the picture below is software simulation) | Reference information [3]

From the theoretical perspective, Patil explains the reason why the twisting can change the way of routine breaks: and the principle of vibration waves (may be referred to as "bending waves") in the bending state. The twisting angle is large enough, the reversing wave is sufficient to suppress the spread of curved waves, and no longer causes the class to break.

The reversing angle is 100 °, the pasta will still break into multiple paragraphs | Reference materials [3]

Another method of breaking the pasta into two sections is called quenching. In short, it is to slow down, boiled frogs in warm water, and fold the noodles slowly.

The experimental results show that the pasta is easier to break into multiple interceptions when the bending speed is faster, then as long as we are slow enough, we can make the pasta fold into two paragraphs.

At the speed of 5 mm/second (Figure A) and 300 mm/s (Figure B)

Comparison of curved sides | Reference materials [3]

The best pasta of cooking output!

In addition to exhausting your effort, physicists will also cook with the posture of research.

Sameh Tawfick, a researcher from the University of Illinois, led the team to study the physical changes such as expansion, softening, and bonding during the cooking process, established an inadvertent expansion dynamic model, and verified it with experiments to verify that it should be verified. Model.

They put the cups with distilled water on the heating plate and heat it. After the water reaches a certain temperature, put the two parallel pasta noodles vertically into the water, and record the changes in the noodles once every time.

Experimental method of cooking pasta | Reference materials [1]

In hot water, the noodles have gone through the physical process of Hygroscopic Swelling. After the water molecules enter the noodles, the noodles also swell.

The simplicity of the noodles as a cylinder, the expansion is mainly reflected in the radial and axial direction: the radial expansion is that the noodles become "thick", and the axial expansion is the "long" of the noodles. Before completely cooked, the expansion in the two directions of the noodles has a quantitative relationship, and the radial expansion is about 3.5 times the axial.

Interests in the water are expanded in radial and axis | Reference materials [1]

Life experience tells us that the softer the noodles, the more softer the noodles, and the more influencing the taste. The hardness is the key factor that affects the taste of the noodles.

In Italian, the most ideal taste of the pasta is called "Al Dente", which literally means "until the teeth", which refers to the effect of the noodles cooked into "hard and soft".

In order to analyze how to achieve "Al Dente", the researchers used dynamic mechanics analyzers to measure the amount of Yang's modulus. The definition of Yang's modulus is the ratio of elastic material and the transformation ratio. To put it simply, the greater the amount of Yang's modulus, the greater the need for it to eliminate it, and the less likely the noodles are, the less likely to cause deformation.

Dynamic mechanics analyzer measured the guidance of Yang's modulus | Reference materials [1]

It is easy to see that the longer the noodles, the softening the noodles absorb water, the amount of Yang's modulus should continue to be reduced, and the experimental results are completely in line with the common sense of experience.

According to the changing trend of Yang's modulus, the researchers divide the cooking noodles into three stages:

In the first stage, the pasta basically maintained the original state, and the amount of Yang's modulus changed less;

In the second stage, pasta changes from glass state to rubber state. The amount of Yang's mold will quickly decrease a few orders of magnitude in just a few minutes (in popular, the pasta is very fast at this stage);

In the third stage, Yang's modulus slowly decreased, and the pasta eventually became a state of completely boiling.

The amount of Yang's Yang's modulus decreases over time, and red and black represent the water temperature of 100 ° C and 80 ° C, respectively.

The curve is the theoretical prediction value, the point is the experimental measurement value | Reference materials [1]

Therefore, if you can measure the amount of Yang's modulus while cooking, you can easily pick it up before the noodles are rotten.

For everyone who does not have professional instruments at home, physicists also give an alternative plan outside the Yang family: look sticky.

In the experiment, remove the two cooked noodles from the water, and you can find that a section of noodles will be bonded together. This is because there are residual moisture between the noodles, and the formation of the curved liquid surface connects two noodles under the action of the surface tension.

Two pasta is connected under the role of water on the surface of water | Reference materials [1]

Researchers have found that the longer the noodles, the longer the length of the two noodles. The experience of cooking noodles also tells us that the noodles are "crickets" for too long, and they are bonded with each other, and they are struggling to eat.

After measuring the changing trend of the bonding length, the researchers proposed the "suggestion" of judging the sense of oral oralness: two noodles can be taken out when cooking noodles, and the bonding length can be measured with a ruler to determine whether it is cooked to " "Al Deente".

The longer the noodle noodles, the longer the length of the bonding between the two noodles | Reference materials [1]

The researchers also said that "the noodles are the same time, but the amount of salt in the noodles is different." It will affect the migration of water molecules inside the noodles, thereby affecting the amount of Yang's modulus and taste of the noodles. Therefore, compared to "time to boil noodles", "gashing length with ruler noodles" will be a more reliable method.

How do you say, these suggestions, the future can be expected ... at least I would rather try it with my mouth instead of using a ruler_ (: з∠) _

The wonderful metaphor of the pasta

Physicists' interest in the past is not only the physical properties of the noodles itself. Because of the shape of the pasta, physicists will also compare certain physical images to the past, so that the obscure physical concept appears to appear image. vivid.

After a billions of years of evolution, a medium -quality star will explode, and eventually collapse into a neutron star. The quality of neutron stars can reach dozens of times the sun, but the volume is squeezed into the size of only one city, which has extremely high density.

The density of neutron stars is extremely high, accompanied by a strong magnetic field | Wikimedia Commons

Assistant professor Matthew Caplan from Illinois University and partners simulate the possible structural images of neutron stars through a computer, and compare these structural visuals to "Nuclear Pasta": Nuclear Pasta):

The foam -shaped distributed structure is compared to the Italian dumplings. The long strip structure is ratio as the Italian surface. The multi -layer parallel structure ratio of pores is made of Wastec cakes, and there is no hole ratio as a thousand levels. These structures will change with the changes in the internal pressure of the neutron.

The structure of the neutron star shell is compared with various Italian pasta | Reference materials [4]

Not only neutron stars, but also an analogy of pasta in another dense celestial body, the study of black holes. Under the action of a powerful non -uniform gravitational field (such as close to the black hole), objects will become very slender because it is like an Italian surface after deformation, so this process is called "spaghettification".

Taking the scene of the human body being swallowed by the black hole as an example, the human body's feet are closest to the black hole, and the head is the farthest from the black hole, so the gravity of the foot is greater than the head. At the same time, the head and feet of the arms and the human body are not in the same direction, and the gravity that is affected will attract the arms to the middle.

In this way, the body stretching in the vertical direction and compressing horizontally, and the human body eventually became a slender strip like noodles. In the astronomical popularization, the classic pictures of astronauts were stretched near the black hole, which is the imaginary image of the human body's facialization.

The illusion of the human body by black hole noodles | NASA

Up to the vast universe, sun, moon, and stars, and down the pots of pans and pans. It can be found in the field of span so large. This is the fun and romance of physics.

Reference

[1] HWANG J, HA J, Et Al. Swelling, Softening, and Elastocapillar Adhesion of Cooked Pasta [J]. Physics of Fluids, 2022, 34 (4): 042105. [2] Audoly b, neukirch s . Fragmentation of Rods by Cascading Cracks: why spaghetti do break in half [j]. Physical review letters, 2005, 95 (9): 095505.

[3] Heisser R H, P, Stoop N, et al. Controlling frame cascades through twisting and queenching [J]. Proceedings of the National Academy of sciences, 2018, 115 (35): 8665-8:

[4] Caplan M E, Horowitz C J. Colloquium: ASTROMATERIALANCE and NUCLEAR PASTA [J]. Reviews of Modern Physics, 2017, 89 (4): 041002.

[5] https://mechse.illinois.edu/news/45445

[6] https://publishing.aip.org/publications/lated-content/physics-models-define-what- maps-dente/

[7] https://pansci.asia/archives/349236

[8] https://news.mit.edu/2018/mit-mathematicians-solve-te-spaghetti-myster-0813

[9] https://improbable.com/2018/08/13/breakthough-snApping-A- SPAGHETTTI-Into-2- Not-3- Pieces/

[10] https://www.liveScience.com/63338-spaghetti-snap-machine.html

[11] https://www.mcgill.ca/newsroom/chaannels/nuclear-pasta-known-substance- universed-289729

[12] https://en.wikipedia.org/wiki/spaghettification

Author: matrix star

Edit: Emeria, You Zhixuan, Odette

- END -