Sunday, January 29

# Science explains why Christmas lights always get tangled | Digital Trends Spanish

One of those rituals that we do in December is to assemble the tree of Christmasand of course, in addition to the decorations, a classic component is the famous Christmas lights that surround it.

The truth is that one of the most intriguing questions is why these lights always end up getting tangled up and science has an explanation.

In 2007, a group of researchers published a study in the journal Proceedings of the National Academy of Sciences (PNAS). For the experiment, they put different lengths of rope inside a box and shook it mechanically so that the ropes rattled like a load of laundry in the dryer. They repeated the process more than 3,400 times and noticed that knots began to form within seconds of turning the box. Throughout the experiment, more than 120 types of knots were formed.

“It didn’t take long for the knots to form, maybe 10 seconds. That surprised us,” said study co-author douglas smith, Professor in the Department of Physics at the University of California, San Diego (UCSD). “We immediately started to see these complicated knots starting to form. Everything went very fast”.

What happened then?: The length of the rope affected the probability that knots would form. Not surprisingly, as the length of the rope increased (the longest length used in the study was 15 feet, or 4.6 meters), the probability of a knot occurring also increased, reaching 100%. guaranteed. The material the rope was made of also had an effect, with more flexible ropes experiencing more knotting compared to stiff ropes, according to the study.

But perhaps the biggest factor that led to knots was whether the ends of the ropes were loose, allowing them to move freely to form tangles.

“The ends are really what make a knot form,” he said. Dorian Raymer, lead author of the study and a former UCSD student. “Sailors probably know best, that you have to control what the ends [de una cuerda] they are doing to avoid knots. Otherwise, the ends can move above or below other sections of the rope, eventually leading to knots.”

And in the case of Christmas lights, having dozens of bulbs sticking out of the cord introduces even more opportunities for tangles.

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