Heavenly Dao Formula

This is a classic air pressure test.

The device with the highest technical content is probably this glass. It was entrusted by Xia Fan to Luo Weiwei to be specially fired with dragon scales. Although it is dark green due to the impurities in the sea sand, it does not hinder its excellent light transmission.

Put four candles in a basin filled with water, light the candles, and put the glass upside down.

In full view, the candle quickly ran out of oxygen and went out.

Then the water level inside the cup rose rapidly at a speed visible to the naked eye.

In less than a few breaths of time, the water pouring into the cup surpassed the basin outside and rose to almost one-third of the cup wall. From a distance, it looked like a new "hill" had risen in the basin.

And before that, the inner and outer water surfaces were still at the same level!

"How did the water... move?"

"It feels like being sucked up by something!"

The children's interest was immediately aroused.

"Everyone may wish to think about why such a phenomenon occurs." Xia Fan looked at the crowd again - in fact, he had the entrustment of arranging the Privy Council among the observers, just to prevent the silence caused by no one answering .

But this time someone gave the answer ahead of time.

"Could it be that what you want to say is that because the gas in the bottle is exhausted, the gas outside squeezes the water surface and pushes the water into the bottle?"

"Correct." Xia Fan followed the prestige with some curiosity, and it was a little girl who caught his eyes. Judging from her location, she should be a guest invited by Fang Xiandao.

To be honest, although this experiment is classic, it is not as shocking as the hemisphere experiment in terms of perception. It takes a circle to understand the principle. The other party seems to be young, but he can quickly think of this level. Could it be - is she also a living dead?

"Then can I ask a few more questions?" Qian Yan stood up from the chair, which made her suddenly fall a bit shorter, "The person in front, please make room."

Probably because they had never seen such an imposing little girl, everyone involuntarily vacated a passage.

"Lord Qianyan..." Fang Yanni's face turned pale.

"Don't worry." Fang Xiandao said soothingly, "The Xia Fan I know is not the kind of person who bullies others."

On the other side, Xia Fan nodded with interest, "Of course, you say."

"Since there is pressure in the air, why don't we feel tired, even if we relax, we won't be crushed?"

"It's the same as this bottle, because there is air in our body, and the inside and outside are just offset. If the air is taken out, the weight is enough to press a person."

"What exactly is air? Does it have a substance? Can it be touched directly?" Qian Yan asked.

If it is the theory of reality in the past, it will definitely avoid answering this kind of question directly, and instead talk about some mysterious and mysterious principles.

"Of course it does." However, Xia Fan did not forcefully change the subject, "You can understand gas as a kind of thinner water, so when the temperature is low enough, it will freeze like water and become visible to the naked eye. "Ice lump" - I think at that time, you may be able to see more intuitively that you are touching a kind of entity."

"Air—can it be frozen?" Qian Yan couldn't help being stunned, she definitely didn't expect to get such an answer, "How low is the temperature?"

"It's much lower than the freezing point. This temperature may be difficult to achieve at present, but as long as you work hard in this direction, I think you should be able to see it one day-isn't the frost formation technique condensing the water vapor floating in the air into ice?" ?"

Qian Yan showed a pensive look, and she raised her head after a long time, "These are just your speculations, right?"

Xia Fan did not deny it.

She hesitated, "In other words...whether this conclusion is correct is still doubtful."

"I know it's really unimaginable. This is also a great joy of studying things: from the details that can be seen everywhere, deduce the principles behind things and apply them to a wider range of fields, even if it is counterintuitive." Xia Fan turned to the high-spirited Students, "Everyone be quiet! I have another experiment prepared that will show you that not only does air fill you up like water, but people can do incredible things with it!"

This experiment is no longer limited to the size of a glass bottle, but takes the world as the stage.

A simple fun experiment of air pressure certainly couldn't satisfy Xia Fan. He tried his best to make this open class the first shot to make the school famous, so he didn't hold back at all.

And to demonstrate the fascination of air, what could be more impressive than a representative machine that combines various aerodynamic studies and represents the conquest of the sky by human beings?

Under his signal, two guards carried a biplane into the school hall.

Although its size can only be said to be at the model level, it immediately attracted everyone's attention with its unique shape - it looked a bit like a kite at first glance, but everyone soon discovered that it was much thicker than a kite, and its size was close to half a person It is tall, and the wings are more than an arm. The thing didn't move a muscle when it was on the ground, and its weight was evident.

The next step is to build a runway about 100 meters long with smooth wooden boards.

Xia Fan originally thought that the key to the biplane model - the electric motor was difficult to polish by hand, but Mo Yun gave him a surprise, the slender iron rod that was used as the rotor, it was precisely the latter who grinded it into shape bit by bit with precise hands . In contrast, the copper wires and magnets surrounding the rotor are just the experience accumulated in the four-wheel drive era, and it doesn't take much work.

It is two sets of indigenous capacitors that provide energy for the engine. They are made of layers of gold foil and lacquered paper, which are also coated with sealing wax to prevent the insulation from being broken down, so that the electric charge does not fly up and down.

To charge the capacitor is a streamer technique. Even after thousands of shock techniques, Xia Fan burned several trial products before he mastered the strength of charging the earth method capacitor.

Of course, he can also hold the wire to directly provide energy for the model machine, but this kind of "wired remote control" is easily reminiscent of a kite, and it inevitably lacks the feeling of freedom and wind.

"What is this?" Qianyan couldn't help asking.

"A vehicle that allows people to fly in the air, but it's just a model now."

"Soaring... in the air? You mean, it can fly?"

This sentence is also a question for everyone, after all, the model machine looks too heavy and clumsy.

"Because the air flows like water, as long as it is used properly, it can also support things that are thousands of times heavier than itself, just like a ship that weighs a thousand tons can only float on the sea." Xia Fan replied with a smile. Seeing that everything was ready, he pulled the switch to connect the circuit.

The propellers at the nose of the aircraft spun rapidly and made a huge buzzing sound!

The motor needs no power assist, it will run at maximum twist whenever power is available.

Driven by the propeller, the biplane began to move forward slowly, getting faster and faster. Until the pressure difference obtained by the upper and lower wings exceeded the weight of the aircraft, it seemed to be lifted up by a pair of invisible hands, and it suddenly left the ground under the incredible eyes of more than two hundred people, roaring into the air!

The scene was silent for a while.

Xia Fan knew that the two sets of capacitors could only run for a few tens of seconds before it would fall to the ground under the pull of gravity. But just these tens of seconds are enough to leave an indelible impression in people's hearts.