Video spoilers history, starting with the blitzkrieg on Poland

A new sky appeared.

In the picture of the sky, a world of ice and snow appeared.

Everyone seemed to be standing on a thick ice lake and playing.

In the middle of the ice lake, a circular ice pit appeared without snow.

The shape of this ice pit is like a pot, sunken.

The overall size of the ice pit is not large, with a diameter of only about two or three meters.

The depth is less than half a meter.

People stood in the middle of the ice pit without even their calves sinking completely.

And the voice of the sky also sounded:
If you fall into a small circular ice pit like this one, it could be the last mistake you ever make.

[Don’t be fooled by the fact that this ice pit is neither wide nor deep. ]

[But once you enter the middle of the ice pit, it is difficult to get out. ]

As if to verify the words in the video.

In many different videos, we can see different people walking in ice pits of different sizes and depths.

They wanted to get out of the ice pit.

It seemed like only two or three steps were needed, but they all failed.

Even though it was just a small ice pit, it trapped them inside.

Whether you walk slowly or sprint hard.

Or lying on the ground trying to crawl out?

They would slide back to their original position halfway because the ice was too smooth.

It was as if some magic was cast on this small ice pit.

Outside the sky.

Western Jin Dynasty.

Sima Zhong saw these people on the sky, trapped in a small ice pit, rolling and crawling, trying many times but unable to get out.

I can't help but worry about these people.

Sima Zhong said:
"Oh my, this ice pit doesn't look that big, how come it's so big?"

"How come that big guy in the video just now, who is so strong, can't get out of this ice pit?"

“I didn’t expect the ice pit to be such a scary thing.”

"I also said that I would go to the ice lake for some fun this winter."

"It seems that we should forget it now."

"As an emperor, the most important thing is to ensure your own safety, don't you think?"

And in the Tang Dynasty.

Li Jing saw this ice pit.

But I don’t think it’s anything great, it’s not difficult at all!

Li Jing, who had extensive combat experience in the north, had naturally seen similar ice pits.

I even once "relived the passion of youth" and played in an ice pit.

As for how to get out of this small ice pit.

Li Jing understands very well.

However, Li Jing did not say it directly, but said to Li Shimin next to him:

"Your Majesty, this ice pit is indeed interesting."

"It reminds me of the time when I was fighting against the Turks. I also played in an ice pit once."

"I have to say, that slippery thing is really fun and interesting."

Seeing the rare childlike smile on Li Jing's old face, Li Shimin also smiled and said:

"Oh? Duke Wei has ever played in an ice pit?"

"From the looks of you, I guess you know how to get out of the ice pit, right?"

Li Jing nodded: "It's actually very simple to get out of this ice pit. The local herdsmen taught me."

"However, since Tianmu Video will broadcast this content."

"I think the answer will be revealed soon."

"How about this, I will not say anything yet, but first see what Tianmu says, so as not to spoil the answer in advance, and then it will be meaningless for Your Majesty to read Tianmu."

Li Jing's idea was quite thoughtful. Li Shimin smiled knowingly after hearing this.

Then, the king and his minister looked at the sky carefully, waiting for the answer to be revealed.

[The video just now shows the once very popular ice pit challenge. ]

[This brother moved left and right, but eventually slid back to where he was. ]

[This young lady fell into the ice pit repeatedly, and her nose was bleeding. ]

[It can be seen that it is not easy for people without preparation and experience to go out. ]

[It is difficult for people to get out of a circular ice pit because the ice surface is smooth and has little friction. ]

[The friction coefficient of ice is only 0.01-0.1. ]

[I can't even grasp it with my fingers, it's like trying to grab a marble with chopsticks, I can't do anything with it!]

[When a person tries to walk out of an ice pit, there is not enough friction between the soles of the shoes and the ice surface to support the weight of the body and the force of moving forward.]

[Causes you to slip every time you exert force. ]

[In addition, the circular structure of the ice pit also increases the difficulty of getting out. ]

[If it is a square pit, you can also use your feet to push against the corners for leverage. ]

[But the circular ice pit has no edges and corners, and there is no support for hands and feet. The higher you go, the more curved it becomes, just like falling into a smooth bowl. The more you struggle, the more you slide down! ]

[The body can easily slide down to the bottom of the pit. ]

[It is for this reason that you cannot do this unless you have extraordinary jumping ability. ]

[Otherwise, it would be difficult for people with average physical fitness to walk out of the ice pit directly. ]

[Many people's first reaction after falling into an ice hole is to try their best to jump out. ]

【This is actually wrong.】

[However, using some physical principles can increase the possibility of getting out of the ice pit. ]

[For example, walking slowly or running in a circular motion along a ramp can minimize the force applied to the slippery surface and reduce the risk of slipping.]

[At the same time, the centrifugal force created by the rotation causes the object to move outward.]

【Thereby helping people to slowly move away from the center of the ice pit.】

[If you have keys, a cell phone, or a belt buckle with you, use it to chisel the ice and create a fulcrum! ]

[You can also untie your shoelaces and wrap them around your hands to increase the friction between your hands and the ice! ]

……

As the video ended, comments started flying out.

"I played this in Harbin. It's very easy to get up."

"Just take off your shoes. I suggest you take off a piece of clothing and lay it on top, then step on the clothing when you go out."

"Slide left and right, keep sliding, like swinging, and you will fall out."

"Won't you be mad if I wear spiked shoes?"

《Ice Pit Challenge: Prickly Ice.》

《It is recommended to wait until summer to go out.》

""Complete Golden Spinner"! 》

《Wait! You just said "centrifugal force", right?》

《Please invite both debaters to enter the arena! 》

《Please choose your team: 1. High School Physics Team, 2. Non-Inertial System Team. 》

《There is no centrifugal force, only centripetal force! 》

"The tongue licks the ice, and then freezes very solidly. Then use the frozen tongue as an anchor, roll out, and then find a way to get the tongue off."

"Bear Grylls taught: put socks on shoes."

After watching the video explanation.

Tang Dynasty.

Li Shimin nodded:
"I see. It is indeed a very simple technique."

"And think back."

"Although I didn't fall into the ice pit, I also found that when I was young, I always felt a force rushing outward when running on a slope like this."

“Maybe this is a similar principle.”

"This kind of popular science video is really interesting." (End of this chapter)