The nail hangs down from the door frame. As Fang Jun releases his hand, it swings back and forth under the pull of its own gravity. This is a simple pendulum.
Everyone stared at the nails swinging back and forth in wonder, and then they were surprised to find that although the swing amplitude of the two nails was different, one was larger and the other was smaller, what was magical was that the two nails reached the other from one vertex every time.
The swing time of the apex is actually the same...
In the inherent impression, heavy objects fall faster than light objects. The greater the swing of the nail, the slower it should naturally be. However, what is presented in front of us is a completely different scene...
His Majesty Li Er was still in a state of confusion. This scene simply overturned his inherent cognition. After being stunned for a long time, Li Chunfeng suddenly slapped his thigh and shouted excitedly: "If it is made with such a device,
By measuring time, wouldn’t it be possible to divide a day into countless even equal parts?”
What is the biggest problem with measuring time?
is an error.
Any mechanism or machine will change all the time due to power, resistance, etc., and errors are inevitable.
But this swinging nail pointed out a clear path for him. As long as the nail swings, no matter the size of the power or the size of the resistance, as long as it is swinging, the time of each swing will be infinitely close to the same.
Let's divide the day into countless parts, then the length of each part will be equal.
Fang Jun was very impressed when he saw that Li Chunfeng understood the principle of this simple pendulum device.
He is indeed the most outstanding astronomer in history, and he will be able to enter the Chinese Academy of Sciences in later generations...
Yes, this is the isochronism of the pendulum.
As long as the lengths of the ropes are equal, the time it takes to complete one swing is the same regardless of whether the pendulum swings larger or smaller.
It is said that this theory was discovered by Galileo, and based on this theory, the first pendulum clock in human history was made. As long as the 21st century, this kind of pendulum clock still exists.
Li Chunfeng touched his palms and exclaimed: "Erlang is really a god!"
On the side, His Majesty Li Er was stroking his beard with a look of relief and admiration, but in fact he was complaining crazily in his heart - Who am I? Where am I? Why can't I understand what they are saying at all?
But as an emperor, he naturally has the majesty of an emperor. The "Son of Heaven" is an otherworldly existence in the world. If he admits that he doesn't understand the meaning of the nail swinging in front of him, wouldn't he look very ignorant?
Sometimes you can confess that you don't understand, and this will be considered as being open-minded and shameless to ask; but sometimes you have to pretend to understand, otherwise you will be considered as stupid and uncarved...
Fortunately, both Li Chunfeng and Fang Jun were very thoughtful people and did not stupidly step forward and ask - Your Majesty, do you understand? Come on, let's talk about it, let me wait and see if Your Majesty really understands...
…
If that's the case, His Majesty Li Er might get angry.
*****
The progress of any subject in the world is a process of accumulation over time and then accumulation.
The discovery of every species in the world can promote an unprecedented revolution...
Fang Jun stood on the ridge of Lishan Farm, with the scorching sun in the sky. The green corn field at the foot of the mountain was spread out like a large and heavy carpet. It was growing well. The corn stalks wrapped in leaves were already hanging down their beards, and they were full.
In the open space opened up on the hillside on the other side, ridge after ridge of sweet potato vines climbed wantonly, and the potato seedlings all over the place were green and tall, covering the open space by the stream below the hillside. Dozens of Fang family servants were bracing themselves against the scorching sun.
Walking through the potato fields, picking off the white, pink, and purple flower buds that just bloomed.
If potato flowers bloom, it will lead to reduced potato production...
Along the mountain road, I walked slowly with my hands behind my back. There were all kinds of fruit trees along the way. The branches were bent under the weight of fruits. Half of Lishan Mountain has become the largest "agricultural research park" in Datang. Grafted fruit trees, American corn
, potatoes, sweet potatoes, peanuts, rice from Nanyang...are laid out layer by layer from high to low.
Fang Jun felt like a king inspecting his territory. Compared with the physical and chemical knowledge of making steel, iron, burning glass and making pendulum clocks, which is quite difficult for him as a "two-handed sword", half of the mountain is planted with
All kinds of food are his favorite.
He knows the habits of each crop and can easily prevent various diseases. He has a thorough understanding of every growth stage, which makes him feel like a fish in water and has everything under control.
…
The tall corns grow vigorously, and the wind blows through the corn fields. From above, it looks like a green sea wave. Being among them, walking on the narrow path surrounded by tall corn stalks on both sides, you feel the coolness and comfort, and the wind blows in your ears.
The leaves rustle.
Fang Jun spent a whole morning inspecting a field of corns. All the corns were growing well, which made him very satisfied.
As long as this piece of corn field has a good harvest in the fall, there will be enough seeds to plant corn crops in the entire idle land in Guanzhong next spring.
Together with potatoes and sweet potatoes, all the people in Guanzhong will be able to obtain enough food by next autumn.
Walking out of the corn field, we stepped onto a slightly spacious path. There was a thatched cottage in front of us. This was reserved for the servants of the Fang family to patrol and guard the corn. These corns were all used to collect seeds, and not a single grain could be harvested.
loss.
Behind the thatched cottage is a canal. The clear water flows toward the low place with a gurgling sound. The canal is planted with ridges and cages of peppers, with thick branches and leaves and abundant fruits.
This kind of thing has to be naturally mature to have more flavor. Off-season vegetables grown in greenhouses look similar and even have higher yields, but they lose their own flavor because they violate their own growth rules.
smell……
A bullock cart was parked in the open space on the roadside next to the thatched cottage. The bullock driving the cart was wagging its tail and leisurely eating the green grass on the ground.
An old man with white hair and beard is sitting cross-legged in the thatched hut, with a tea set and a small stove beside him. He is holding a cup of hot tea, feeling the smell of fresh grass leaves brought by the wind blowing through the corn field, squinting.
He closed his eyes and seemed to be enjoying himself...
Fang Jun quickly quickened his pace and walked over. When he arrived outside the thatched cottage, he bowed and saluted, and said respectfully: "Senior, please say hello."
The old man turned around and saw Fang Jun. His face covered with age spots showed a kind and warm smile, and he nodded slightly: "Erlang is here, come on, come and sit here and have a cup of tea."
Fang Jun took off his shoes happily, and there was already a mat spread on the floor of the thatched cottage...
An old servant who was not young at all hurriedly went to get water from the stream, then boiled it on the stove, made another pot of tea, placed it in front of the two of them, took out a food box from the ox cart, took it over, and opened the lid
, took out a few beautiful plates and put a few beautiful snacks on them.
Fang Jun poured tea for the old man and said with a smile: "On a summer outing, you can avoid the irritability of the city and enjoy some fun in the fields. Mr. Chongyuan is so good-humored that he is really the envy of the younger generation."
This old man is Kong Yingda...
"Chongyuan" is Kong Yingda's name. Only close family friends and nephews can call him "Chongyuan Gong". Others do not have this qualification.
However, Fang Jun and Kong Yingda have always been familiar with each other. This great scholar not only followed Fang Jun on overseas trips, but also played mahjong together at the market. He was also a serious "Mahjong friend" and they were very close to each other.
When Kong Yingda heard Fang Jun's compliment, he smiled and sighed: "When I was young, I always complained about being burdened with trivial matters and having too many things to do. But when I get old, I can't keep up the energy to do anything, so I can only wait to die.
Only then will you realize that if you can keep busy, it would be a kind of happiness.”
Filling the tea cup in front of Kong Yingda, Fang Jun asked: "Qujiang Pond is covered with lotus flowers, cool breeze blows, Zhongnan Mountain has beautiful mountains and rivers, and lush trees. Mr. Chongyuan will not go to these two places for sightseeing.
Why did you come to this corn field? Although it is green, it is still a bit monotonous."
"hehe."
Kong Yingda reached out and picked up a piece of pastry and chewed it in his mouth, then took a sip of tea, put down the tea cup, opened his turbid old eyes and looked around at the continuous field of corn outside the thatched cottage, and said quietly: "I have traveled all over the country in my life, including the north and south of the Great Wall.
, I have experienced countless steep peaks and beautiful mountains and rivers, but I have never felt that any place can compare with a field of corn. The beauty of the mountains and rivers depends on the foundation of the place. When the weather, time and place are combined into one, it is a scenic spot, but
There is always a lack of popularity. How can there be beauty in a thin and rigid landscape?"