In order to understand the mystery of opening the headset cable, scientists put the rope in the box more than 3,000 times

Review expert: Luo Huiyue

Associate Researcher of the Institute of Physics of the Chinese Academy of Sciences

A beautiful day, when you suddenly want to pull out your headphones from your pocket to listen to music, you will always find that you don't know when the headset cable is wrapped together!

It is also the line. The power cord and the data cable are rarely knotted in the bag. Why is the headphone cable so easy to knot? Is there a small fairy in your pocket, squatting in your pocket every day and waiting for the headset cable?

What tangled the headphone cable together? Let's understand the theory of twisting

Newly knotted, as the name suggests, is a knotted rope in the end, which may have distorted intersections. As for KNOT Theory, it is a branch of topology to study the topology characteristics of New knots. In the theory of twisting, Prime Knot refers to the extraordinary new knot that cannot be decomposed.

All crosses are less than or equal to 7 suits.

Each plain knot is mainly marked with cross -numbers. Subunn knots with the same cross number can be further distinguished with different settlements.

Source 丨 Wikipedia Encyclopedia

The theory of New Jie is a study of how to embed several rings into mathematical branches in the three -dimensional Oushi space. The object of its research must be curve, and it is a curve in the three -dimensional space, so we can attribute the problem of the headset cable to the new knot theory. In the New Jet theory, if one knot can be converted into another without separation, it is considered that the two knots before and after conversion are equivalent.

As early as 2007, physicist Douglas E.Smith and undergraduate student Dorian Raymer had studied the feasibility of applying the new knot theory to rope knotting. Funny Nobel Prize in Physics.

The experiments were packed in a transparent box of different lengths, hard and hard ropes, and rotated the box with various speeds for 3415 experiments.

Experiments have found that soft ropes are easier to knots -from our daily life experience, we can know that soft ropes, such as wool and needle threads, can be united by just pinching. In contrast, the power cord and the data cable are thick and hard, it is difficult to form a complicated knot as the headset cable.

The experiment also found that a rope less than 46 cm long was almost won't knotted after being sealed in a rotating box for a while. But from 46 cm to 150 cm, the probability of formation will rise sharply. If the length of the rope exceeds this length, the probability of knotting is basically stable at 50%.

Plusal probability-rope length (m)

Source 丨 sciencealert

You might as well measure your headphone cable, and you will find that it is about 150 cm long. As can be seen from the above figure, the vertical axis indicates the probability of knotting, and the horizontal axis indicates the length of the rope; 140 cm is 1.4 meters, and the 1.4 horizontal axis corresponds to a number between 0.4 to 0.5 of the vertical axis, so we can see that it "at least the least "There is almost a probability of about 50%. Why is it "least"? Because the headset cable can be regarded as a Y -shaped rope, there are three lines, and the weight of the headset at both ends is heavier than the headset cable. It is easy to drive the headphone cable, which further increases the chance of wounding the headset cable.

They also found that the width of the square box doubled, and the probability of knotting was slightly higher, but the reduction of 33%of the width of the box would reduce the probability of knotting sharply.

Finally, there is a schematic diagram here to show how a line starts to rotate in a rotating box. Studies have shown that one end of the rope only needs to cross twice with the other end to spontaneously knots:

Source 丨 sciencealert

You can rest assured: the formation of these knots is indeed out of physical reasons, not because of some supernatural power.

How to avoid the headphone cable wrapped?

From the experiment, we can summarize the following conclusions:

More flexible materials are often easier to knot.

So if the headset cable is harder, the chance of knotting can be reduced.

The more the headset rolls, the more likely it is to be entangled together, the more likely the possibility of knotting.

The pocket on the chest is usually smaller than pants pockets, so put the headset in the pocket on the chest may be better than placing in pants pocket.

The larger the box, the more you knot.

Therefore, if you put your headphones in a small pocket instead of a big bag, the headset cable may have less opportunities to knot.

Source 丨 pixabay

Therefore, if you want the headset cable not to be knotted, you can try the following three methods:

1. Binding the headset method: artificially wrapped the headset line tablange, so that it is not easy to move, and it is not easy to knot.

2. Exposing the head of the machine: The two ends of the headphones are exposed to the outside of the pants pocket. As long as the headset head does not shuttle between the line, the light headset cable will not form a circle by itself.

3. Storage method: Put the headphone cable in a small box specially used to install the headset cable.

Is the knot of the headset cable be unlocked by yourself?

The answer is yes, but only when the headset is returned along the path of the knotting along it in the vibration. However, this probability is very small. Generally speaking, objects are more inclined to develop from orderly to disorder. But to return from orderly to order, the cost of energy is usually required.

In other words, knotting is a more stable ending than solving, and the headset cable is naturally more inclined to the result of "knotting".Look at another angle -the outer skin of the headphone cable is usually made of TPE material (thermoplastic elastic body). This material is elastic and small.Related and inversely proportional to its hardness, that is, when TPE's hardness increases, the friction coefficient will decrease.This means that when the headset cable is wrapped together, these knots are more difficult to open due to the existence of friction.

Source 丨 pixabay

Now, the wireless Bluetooth headset has gradually become a new favorite of people. Since there is no line, there is no trouble of knotting.

But then again, if you find that your headphone cable is knotted, why not take the opportunity to study these knots before your mood becomes irritable?

Alexander Great: What kind of knot?Eat my sword!

Source 丨 Wikipedia Encyclopedia

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