Soon, the soldiers found ropes, hoes, pickaxes and other tools, and under Liu Zhi's analysis, they excavated in front of the boulder. Pen "Fun" Pavilion www.biquge.info

They didn't dig indiscriminately, but dug a little shallower near the boulder, and the deeper they dug back, some people found a wooden stick with the thickness of an arm, about a zhang long, and they stuffed it under the boulder, and then stuffed a small stone under the boulder.

The soldiers were still busy with their work, and the wide ditch outside had been dug several feet away, and the soldiers had spread a layer of wood of about the same size and thickness on top of it, and then poured a layer of grease on the wood to make the wood extremely smooth.

The soldiers whispered one by one, not knowing what Liu Zhi was doing.

Luo Shixin and Fang Xingtian also looked confused, and they couldn't figure out which one Liu Zhi was going to make trouble!

Liu Zhi didn't explain, and after the soldiers got it right, he walked up slowly, and he didn't warm up, not like Luo Shixin roared to vent his emotions, he just gently reached out and held a section of the high upturned wood, and then gently pulled down, the boulder weighing tens of thousands of catties was passive, and along the track dug by the soldiers before and the wood laid down, the speed of the boulder sliding faster and faster, so that the onlookers let out a burst of exclamation.

After the boulder rushed out of the laid track, they felt incredulous, and several soldiers in charge of measuring immediately ran over to measure, and after some measurements, the number they reported made everyone gasp!

"More than fifteen feet away!"

Fang Xingtian's face became serious, and Luo Shixin's face became even more unbearable, he couldn't have imagined that Liu Zhi, a person who seemed to be powerless, would actually use such a method to pry such a heavy object away, which, this was beyond his comprehension.

"Did you all see it? Sometimes solving problems is not just by brute force, and if you use your mind more, there may be a better way! ”

He explained: "Anyone who can tell me what techniques I have just used, or what you don't quite understand about what I just did, can ask them now, and I will explain them to you if there is a problem, don't hold it to yourself, then you may never get the right answer." ”

His words made the onlookers eager to try, and many people really didn't quite understand what he had just done.

A soldier stood up and said to Liu Zhi, "Mr. Liu, could it be that the long stick in your hand just now was an immortal spell?" Why is it that a boulder weighing 10,000 pounds is like a thin piece of paper under your hand, so easy to pry? ”

Liu Zhi was stunned in his heart, this guy thinks of himself as an immortal, and he also has an immortal law, how can there be any immortal law in this world!

"This question is good, if anyone else has a problem, say it together, I can solve it for you!"

Liu Zhi's encouraging attitude finally opened the conversation box, and asked him gossipily, some asked him why he wanted to dig down instead of above, some asked him why he dug straight instead of horizontally, and some people asked Weiha why he put the small stone so close to the boulder, why not put the small stone away from the boulder.

These problems are actually very uncommon, although Newton was woken up by an apple, the world did not know Newton's laws, but a common sense is that things are thrown into the air, that will fall, and an ancient Chinese saying that water flows to a low place, which can be called the ancient version of Newton's laws, so Liu Zhiren dug up the boulder underneath, that is, to use the gravity difference to do work, so that the gravitational potential energy of the boulder is converted into kinetic energy.

These things are simple to say, but to explain to everyone, it is not a simple thing, Liu Zhi spent a long time, on the ground to explain the diagram, and finally demonstrated it, everyone then understood, as for the formula of Newton's laws, Liu Zhi thought about it or forget it, it was too troublesome, they definitely couldn't understand it.

This truth is like two armies facing each other, it may be difficult to win head-on, and there will be a lot of losses, so one side decided to deceive, feign defeat on the battlefield, lure the other side to pursue, and then drag them to a canyon, ambushes are arranged on both sides of the canyon, and the ambush soldiers have prepared a large number of rolling wood stones, and once these rolling wood stones are released, they will cause a serious blow to the enemy, and the higher the height of the valley, the higher the position of the ambush, then the stronger the power of these rolling wood stones falling, The more lethal it will be to the enemy. ”

"But this is not absolute, there is another important factor that needs to be examined, that is, friction, everyone stretches out two hands, each picks up a stone, one hand is placed directly above the stone, and then press the stone to the ground hard, and the other hand pushes the stone, isn't it difficult?"

After everyone tried it, they all nodded, and Liu Zhi continued: "Now, which of you will let go of the hand that is pressing the stone, and then push the stone, is it much simpler?" ”

The soldiers did as they were told, and it was exactly what Liu Zhi said, but why was this? The soldiers were puzzled.

"This is friction, friction is such a thing that I have told you for a long time and I guess I can't tell you clearly, but I tell you so simply, when a heavy object falls from the valley, the smoother the ground, then the more powerful this rolling wood stone is, because what he does is accelerate the movement, but if the slope is potholed, although the rolling wood stone is also accelerating, but compared with the rolling wood stone on the flat terrain, its speed is slowed down a lot, so the power is naturally a lot less. Therefore, for the generals, they should observe the terrain more and learn to judge where it is most beneficial for them to fight, so that if they really fight, they will suffer the least losses and the greatest possibility of victory. ”

"Okay, now let's talk about the effect of my wooden stick before, many people may be curious!"

"In fact, its principle is very simple, that is, the principle of leverage, I used the height difference, my strength amplified, this is like a seesaw, the heavy person sits on the short end, and the light person sits on the long section, so that the bar can be balanced enough, we use a lot of things in the principle of leverage in our lives, such as the most common - scales! This thing is also the principle of levers used! ”

The explanation is very boring, and they can't understand it, so Liu Zhiran and they each found a small wooden stick, and then did their own experiments, the content of the experiment is very simple, everyone finds a stone that is not big or small, and then puts a prominent thing on the place near the stone, divides the wooden stick into two sections, the front section is short, the back section is long, and then gently press the back section, and the stone in front is easily pried up.

Liu Zhisheng was afraid that they would forget the original intention of the experiment, so he hurriedly said: "Okay, now let's change the middle fulcrum and move it a little back, yes, let it be a little farther away from the big rock, close to your own hand, okay, now let's try it again and see how the effect is?" ”

The soldiers did as they were told, and sure enough, although they were able to pry it up this time, compared to the ease and simplicity of the previous time, this time it was obviously more laborious, and some soldiers who found relatively large stones couldn't even pry it up at this time.

The soldiers were puzzled, why the things that used to be good and very labor-saving before, at this time they would be so difficult to use, and they became so laborious, they scratched their ears and cheeks one by one, looking very puzzled, and some fiddled with the stones and sticks in their hands, not knowing what the problem was.

Liu Zhi smiled: "Don't you think it's strange, why is the feeling this time very different from the feeling just now!" ”

The soldiers nodded, their ears pricked up to find out.

"Actually, this thing is divided into situations, there are three situations in this thing, mainly depending on the position of the small stone in your hand, everyone pay attention!"

He also picked up a wooden pipe, a small stone and a large stone, Liu Zhi first placed the small stone close to the big stone, and then said to everyone: "This is the first time we have tried the situation, in this case, everyone see, I have completely pried up this big stone!" ”

Liu Zhi pressed it lightly as he spoke, because the stone was not very heavy, so under his external force, it was quickly pried up, and it was completely off the ground.

"You must have a feeling, in this case, it's actually not very difficult, but you may not have noticed, you see, this stone here was completely pried up by me, but the height of its rise is not high, and the position of my fingers here, the height of the stick on this side is relatively high, which shows that this is a labor-saving lever, that is, with less force and greater displacement in exchange for a larger weight and less displacement on the opposite side. Let's remember a truth, that is, the closer you put this small stone, that is, this fulcrum, the closer you put it to the object you want to move, that is, the stone that we move, the less force you need to use, but the lower the height you need to pry up the object you want to prie, and the more you put it back, the more force you need to use, and the height of this object will get higher and higher, do you understand? If you understand it, do some experiments yourself! ”

Taking advantage of the soldiers' interest, Liu Zhi stepped up to let them understand it.

Luo Shixin felt that he seemed to have gained a lot of knowledge, so he ran over and asked, "Sir, what is the use of this thing after we learn it?" ”

Liu Zhi smiled slightly and said Archimedes' famous saying: "Give me a fulcrum, I can pry the earth!" ”

"Huh? Earth, what is Earth? ”

Luo Shixin didn't know what the earth was, and explained to him that the earth is round, and what we have under our feet is the earth, and he must also understand that he can't, so Liu Zhi didn't waste his tongue, but just said to him: "Shixin, this thing can help you save a lot of effort, the reason why I talk so much is not purely to let you understand the principle of a lever, but I hope you can read more in the future, use your brain more, sometimes a good idea is much better than leading troops to rush and fight, do you understand?" ”

Luo Shixin is a brave general, very loyal, which makes Liu Zhi have a good impression of him, in history Luo Shixin has worked with Pei Renji, has been taken care of by Pei Renji father and son, he has always been grateful for this matter, after Pei Renji failed to assassinate Wang Shichong was killed, Luo Shixin also paid for the bones of their father and son to be collected and buried in Beibi Mountain outside the city, and later he himself died in the battle of Luoshui, according to the entrustment of his life, he was also arranged by Li Shimin, the king of Qin, to be buried with Pei's father and son, and were buried in Beibi Mountain.

Luo Shixin is actually the prototype of Luo Cheng in the Romance of the Sui and Tang Dynasties and the Tang Dynasty, but in the world that Liu Zhi crossed, there are both Luo Shixin and Luo Cheng, which is a very surprising thing.

Although Luo Shixin was not very smart, his reaction was not bad at all, as soon as he heard Liu Zhizheng talking to him in a tone like an entrustment, he immediately reacted and asked, "Sir, you, are you leaving?" ”

Liu Zhi patted the dust on his hands, patted him on the shoulder, and said: "There is no banquet in the world, gathering and scattering, naturally there are gatherings and scattering, so I am indeed ready to leave!" ”

Luo Shixin suddenly became sad, his eyes were a little red, and he said to Liu Zhi: "Sir, don't you stay to help Brother Qin?" Brother Qin also said before that he would prepare a surprise for you, do you know? ”

And this thing? Liu Zhi didn't know, and Qin Qiong didn't tell him, okay, Qin Qiong looks serious on weekdays, but he didn't expect to engage in these fancy intestines behind his back.

"Oh? What's the surprise, don't lie to me? ”

Luo Shixin couldn't help but be excited, and seeing Liu Zhi put on a distrustful expression, he hurriedly said: "Brother Qin said, Mr. is a literati, and literati should have taste, so people have prepared a big mansion for you outside the city, with rockeries, a study, and a lot of books, Brother Qin also said, saying that Mr. Liu, you have a detached personality, these mundane things can't get into your eyes, but the current conditions are difficult, and he can't get better things, these things are still searched by him from the treasury of the previous Tamluo Kingdom, In addition, there are only so many of the merchant ships of Silla and Fusang that he bought when they came and went! ”

Liu Zhi smiled bitterly and shook his head, suddenly feeling that Qin Qiong's big black coarse also had a delicate side, the reason why he didn't say it in person when he said goodbye to him was that he was afraid that he was worried that he would be reluctant and guilty in his heart, and he would not go well, so he simply didn't say it, this Qin Qiong was interesting! (To be continued.) )