High altitude diving joke

In the classic film True Lies starring Schwarzenegger, a man was cornered by Schwarzenegger on the roof of a tall building. He was cornered and rode his motorcycle to the swimming pool on the roof of another low-rise building, which surprised Schwarzenegger. Many movies, such as Young Soldier, Jedi Knight, etc., have the plot of high-altitude diving, such as high-rise diving, cliff diving, and even more exaggerated plane diving. Every time I see the protagonist jump into the water at a very dangerous moment, my brother's mood will suddenly relax, because the next shot must be that the pig's feet are above the water and nothing happens.

"Diving" can be said to be a halo in the film industry, similar to the halo of the protagonist, which means everything is OK. But can diving really be unscathed? In fact, we were all fooled by the director! In life, "scuba diving" is a thrilling extreme sport. In addition to model performance, divers should also ensure that their feet enter the water first. Some people want to say that when you are on the platform of the swimming pool, you can jump as you want. There is no danger at all. Don't track and field athletes dive first?

But do you know that the highest diving in track and field is 10 meter? There is a platform in the swimming pool. You can measure it with a ruler. This isn't scuba diving at all, it's just for children. You know, if the diver's head falls into the pool first, it will cause a serious concussion, and even skull fracture may die instantly. If people jump into the water, they will be killed. Do you think it's impossible? Let's look at an example:

On the cliff of Ma 'anzhai in Guanzhi Mountain, Fujian Province, a diving invitational tournament was held. There used to be a 28-meter platform, but due to the recent lack of rain, the lake dropped by 2 meters, which means the diving height became 30 meters. The first German female athlete, who entered the water at an inclined angle, patted her back on the water and was sent away by an ambulance. Another German male player was caught by water on his side, and his right skin was scratched by water, and he soon bled and bruised. Does it sound dangerous, and it's only 30 meters, not what we think.

As we all know, high-altitude divers must undergo strict training, and only 35 people in the world are engaged in extreme high-altitude diving. According to the diving world, the platform for high-altitude diving usually cannot exceed 24.4 meters, which is the highest diving height that can be achieved without harming human body. Even so, the world's highest diving record is as high as 6 1 m (about 20 stories high), but the diver also broke his spine. The principle is that water is incompressible, which is a physical fact. If you put your hand into the water slowly, it will run away. If people hit the water fast enough and the surface area is large enough, there will be no time for the water to be removed. Because it can't be compressed, falling into water is the same as falling into cement.

The acceleration of gravity is caused by the gravity of the earth. The higher the height, the greater the speed at which people reach the water surface, the greater the impact with the water surface and the greater the force on people. Of course, it depends on your contact area with water. The larger the contact area, such as horizontal drop, the greater the force; If we go in, the resultant force will be very small. Abroad, someone did a crazy experiment, throwing two dead pigs (120 kg) from a height of 50 meters into the concrete floor and water. The pigs on the concrete floor are basically broken, and the pigs in the water have five fractures. They threw another pig into the water from a height of 200 meters, causing more than a dozen fractures, including a broken rib inserted into the liver.

The conclusion of this experiment is that these people are abnormal (psychological conclusion) Diving at high altitude will kill people (physical conclusion). Of course, due to the existence of air resistance, it is impossible for people to accelerate all the time when jumping from a height. According to the data of paratroopers before opening their umbrellas, we can know that the maximum speed that people can reach under wind resistance is about 53m/s (190.8km/h). Although you can't speed up all the time, the end of falling into the water at 190 km/h is definitely worse than the end of throwing a dead pig at 200 meters. The reality is cruel, and water is not as weak as we thought. The hero jumps from a cliff or plane to a lake or sea, and the moment when the human body touches the water, it is like touching the concrete floor. The water will not disperse as expected, but it will resist high-speed impact. (We will talk about "Can bullets hit people in water?" )

So don't try scuba diving (especially remind you to double-click 666 live). Don't think you will be as safe as in the movie. The higher you dive, the closer you get to jumping on the concrete floor.