I make a popular science video and all the emperors learn from it!

[Train science popularization completed.] 】

[Start popular science.] 】

[2. Modern means of transportation. 】

[4. Glider. 】

[A glider is a fixed-wing aircraft that is mostly weightless than air without a power plant. 】

[It can be towed by an airplane, towed by a winch or car, and can also be slid down a high slope into the air. 】

[In the absence of wind, the glider relies on the weight of its own gravity to gain forward momentum in the gliding flight, and this unpowered gliding flight that loses altitude is called gliding. 】

[In updrafts, the glider can fly flat or elevated like an eagle spreading its wings, often referred to as soaring.] 】

[The successful development of the glider has a lot to do with the failed attempts of the ancients. 】

[From ancient times to the present, human beings have been dreaming of one day being able to fly into the sky. 】

[Fly freely like a bird.] 】

[The ancients were very confused about the innate and magical ability of birds, thinking that humans must also learn to fly. 】

As a result, the ancients did many things that seem ridiculous to us today. 】

[Human beings' worship of birds is reflected in many myths and stories in ancient and modern China and abroad. 】

[In ancient China, people created the image of a Pegasus, with wings as strong as an eagle on both sides. 】

[The sun god of ancient Greece was also depicted wearing a winged hat and flying shoes. 】

[In addition to this, there are many legends of 063 such as the flying carpet in "Arabian Nights". 】

[However, human beings do not stop at fantasy, there are many pioneers who seem to be fools, and countless amazing attempts have been made. 】

[More than 1900 years ago, a "pilot" of the Western Han Dynasty held an air show in Chang'an, the capital at that time. 】

[This man made wings out of the feathers of a large bird, and it is said that he flew hundreds of paces.] 】

[But there are also people who are not so lucky.] 】

[A young man named John Damian made a bird-like wing out of chicken feathers. 】

[He hopes to use this interesting pair of wings to fly from Scotland to the country of Fa.] 】

[One day, he confidently stood on the high wall of Stirling Castle in Scotland, spread his wings, flapped and jumped......]

[The miracle did not happen. 】

[As a result, he fell to the ground and broke his thigh bone.] 】

[What is especially ridiculous is that he does not think that his behavior is stupid, but blames the flight failure on not using the eagle's feathers for wings.] 】

[Because he thinks chickens belong to the ground birds that cannot fly.] 】

[In the 17th century, a Turk made a pair of wings and jumped from a tall building. 】

[It is said that I was lucky enough to fly several kilometers away.] 】

[It's another Turk, but he doesn't use wings.] 】

[He puts on a wide cloak, which is supported by hard branches, hoping to fly like a bat.] 】

[During the flight, one of the branches inside the cloak broke, and the cloak could not be opened.] 】

And he fell to the ground and died. 】

[Some people think that their arms are weak, and they can't fly to the sky by flapping their wings with their arms.] 】

[So, some people tied their wings with their legs and tried to fly with their feet.] 】

Leonardo da Vinci, a famous artist of the Italian Renaissance, observed and studied the flight of birds and bats, and designed an ornithopter that flapped its wings with its pedals, but it was also unsuccessful. 】

[Why can't humans fly, even if they have wings like birds?]

[The reason is simple, humans do not have the developed chest muscles, the fast heart beat and metabolic function like birds, and they do not have a smooth streamlined body like birds. 】

[A pigeon is about 340 grams, and the flight power emits is 18.8 watts, which is equivalent to 55.1 watts per kilogram of body weight, and its pectoral muscles make up about one-fifth of its body weight.] 】

[The best human athlete can emit 367.5 watts, which is only 5.3 watts per kilogram of body weight based on 70 kilograms, less than one-tenth of the pigeon.] 】

[If you want to fly only by your own strength, you need to grow 15 kg of pectoral and arm muscles, and the bones in your chest need to protrude 1 meter outward. 】

[In addition, the human heart is weaker than that of birds (AICJ.).] 】

[The human heart accounts for only 0.5 of the whole body weight, but the heart of the vulture bird accounts for as much as 8.] 】

[A small hummingbird that can do many flying stunts, and its heart accounts for 22 of its entire body weight. 】

[From this, people can conclude that:] (If you read a violent novel, you will go to Feilu Novel Network!)

Man cannot fly with his wings by his own strength. 】

[Looking at the ancients from the perspective of the present, you may laugh at how stupid and ignorant they were. 】

[In fact, many of them were the most learned people of their time in the era in which they lived, and it is precisely because of these brave pioneers that we humans have succeeded in flying today. 】

[Ornithopter:]

[Ornithopter, also known as thopter, is an aircraft whose wings can flutter up and down like the wings of birds and insects, and is heavier than air. 】

[In this scenario, the flapping wing not only generates lift, but also produces forward propulsion. 】

[Since ancient times, many people have tried in this regard. 】

[The ornithopter wings designed by modern people are made of various synthetic materials, but the "wings" of the ornithopters of ancient people are made of authentic bird feathers, and the "fuselage" is a living person. 】

[So far, there have been many designs of ornithopters, but due to the problems of control technology, materials and structure, the ornithopters are still in the stage of model making and design. 】

[Interestingly, there is no intention to insert willows into the shade.] 】

[The ornithopter was unsuccessful, and when people used manpower to conduct flapping wing flight tests, another kind of aircraft was derived - the glider. 】

【......】

As soon as this popular science came out.

The ancients who dreamed of sticking feathers into their bodies and flying into the sky shattered their dreams!

"No way! Man must be able to fly with wings just like a bird!"

"Yes, people must be too fat! If you are thinner, you will definitely be able to fly!"

"I feel like the wings are too small..."

"Brothers, don't be tough, the light curtain has said the reason, why don't you believe it, don't blame others for falling to death. "

"Bad! I can't say the same thing, but later generations can develop gliders, and they have a lot of credit. "

"That's right, let them try it slowly, let's see what a glider is. "

“..."

[Popular science continues.] 】

【...】。