In the opinion of a master, it is better to be taught to fish than to be fished, and he is about to get these things, which almost has a huge effect on the breakthrough of the bottleneck of his own refining, and he also takes advantage of it.

Xu Cheng pays attention to real interests, such a bottle in his hand is almost equivalent to a big killing weapon, not to mention that he is invincible in the realm of enlightenment, but with this self-preservation, at this moment, the two foxes, one old and one young, each looked at each other and smiled, and they were all a little satisfied.

The more Master Yi looks at this Xu Cheng at this moment, the more pleasing it is to the eye.

At this moment, he stretched out his hand and wiped it on his white beard a few times, raised his eyes, but he was embarrassed to pick up Xu Cheng like that Li An again, and he also found the topic with some meaning: "What are the bottles you made for?"

Xu Cheng replied with a smile, at this moment, the meaning of the old man, he had already relaxed his mind, and said without being humble or arrogant: "Water and fire bottles." ”

"Huh?" said Master Ichi, frowning.

Xu Cheng explained: "The two bottles of yin and yang can't be successful, so I can only retreat to the second, although it still seems very far away. ”

"I see, one yuan of heavy water, but it is good for Nanming to get away from the fire. A master said in a low voice, with a thought in his eyes, "This is also bùcuò, from the way of water and fire to the way of mutual restraint from the day after tomorrow, and the innate yin and yang avenue of derivation, it is also a tricky way, but Nanming is away from the fire."

"Wait", Master Yi's eyes suddenly lit up and he remembered something.

Xu Cheng waited quietly.

A master took out a paper crane from his hand, stretched out his hand, and suddenly a little black ink suddenly gave birth to the void, and then bounced towards the paper crane, the paper crane was floated by the black ink, and in an instant, the whole crane turned into a huge and white white crane, and disappeared without a trace.

"You're lucky. A friend of mine accidentally brought out half a volume of Taoist books from a secret realm, the book was mixed, but it was not useless, and it recorded the range of a Nanming away from the fire, so"

The wind came, vaguely with cranes,

Xu Cheng saw that the white crane had turned into a paper crane on the top of the entire mountain at this moment, and it fell into the hands of a master, and at this moment a master frowned and said: "Even the mountain gate of other people is not jìnqù, but it was stopped by the Taoist boy and said that he was visiting a friend." Master Yi's voice was low and he felt a little embarrassed, which made Xu Cheng feel a little surprised.

"It's okay, I'll just wait, it's always better to have a way like this than nothing is nothing. Xu Cheng performed a salute, and said in a low voice while saluting, his voice was full of feeling, which made the master feel relieved when he heard it, but he took this matter as a matter to do.

At this moment, the sun has set, Xu Cheng is not a person who does not have etiquette, if he does not leave at this moment, then it is a little rude, I am afraid that he will not get benefits, and he can accept it when he sees it at this moment.

Xu Cheng saluted and said, "Forgive my nephew for being rude, I have to leave first at this moment." At this moment, Xu Chengdao's voice was very steady.

Master Yi nodded, raised his head and looked at Xu Cheng and said, "Okay." You come back tomorrow, by the way, I taught you this matter, don't make a show, you want to zhīdào Mu Xiu in the forest wind will destroy it, this kind of truth, I think you also understand. ”

Xu Cheng nodded and walked down the mountain.

A day later

"Energy is neither created nor disappeared out of thin air, it is simply transformed from one form to another, or transferred from one object to another, while the total amount of energy remains the same. Xu Cheng whispered to the master and explained what the law of conservation of energy was.

A master crane has a childish face, and suddenly feels a little embarrassed when he listens at this moment, grabs the beard on his chin and says, "Wait, what is energy?" Master Yi looked at Xu Cheng with his eyes, like an obsessed child.

Xu Cheng not only thought of a sentence, he was obsessed with the Tao, almost a demon.

If the outside world thinks that a master of refining will have such a behavior at this moment, it will really be incredible, but Xu Cheng understands that anyone who has extraordinary achievements in a field is an idiot, and there are people who can make a flute sound and resound through the sky, and when they meet a beggar who plays the flute on the side of the road, if they find their strengths, they will also plead in a low voice.

That's an obsession.

If a master does not have such an obsession, he will not be able to become the most outstanding refining master in the region. Such an existence, even if the head of the house sees it, he has to give up a few points.

Xu Cheng understands that he understands, but he will also be impatient, and at this moment he scolded a little: "Energy you understand as the origin of all things, just like língqì, but it is more pure than língqì, everything is there, fire is energy, water is energy" Xu Cheng's voice was slightly louder.

The little Taoist priest covered his eyes at the moment, and he was a little worried about what bloody scene he would see, because in his impression, no one had ever dared to talk to his master like this, and it was a bit like the night before the storm.

But what the little Taoist priest saw was only that master, smiling flatteringly at the moment, and constantly nodding.

Xu Cheng was naturally embarrassed, so he told some things he had learned: "Energy is a measure of the transformation of material motion, referred to as "energy". Everything in the world is in constant motion, and among all the attributes of matter, motion is the most basic attribute, and all other attributes are the concrete manifestations of motion. Energy is a measure that characterizes the ability of a physical system to do work. There is a formula: ΔU=Q-W. ”

Master Yi nodded again and again, his eyes were a little confused about where Xu Cheng and such a thing came from, it didn't look like he could realize it, but after glancing at Xu Cheng, he didn't dare to ask at this moment.

With such a posture, the little Taoist priest almost had his eyes flying out.

"What is this ΔU=U2-U1?" Master Yi looked at the formula that Xu Cheng wrote on the paper with a brush, his eyes were even more confused, but he became more and more interested, he understood that the main event was coming. At this moment, the voice became more and more excited.

Xu Cheng rolled his eyes helplessly, he had been here since the dawn of the day, but at this moment, he had always been telling the story, so it would be so, but Xu Cheng still had a little bit of pride and a very subtle sense of refreshment in his heart.

A good teacher is talking about the state of Xu Cheng.

"Q is the amount of heat absorbed by the system from the environment during the process; is a mathematical expression of the first law of thermodynamics. ”

A master couldn't help but interrupt: "What is this heat science, and what is this skill?"

Xu Cheng suddenly scolded: "Wait until I'm done!!"

The little Taoist priest now looked at Xu Cheng with stars in his eyes, and felt in his heart that Xu Cheng, who was wearing a water and fire Taoist robe at the moment, was much more majestic than the head of the sect, and even almost at the level of the elder Taishang.

Master Yi suddenly didn't dare to speak, and his ears stood up at this moment.

"U is a state function, i.e., the value of ΔU depends only on the beginning and final states of the system, and has nothing to do with the specific process that the system goes through from the beginning state to the final state, wherein Q and W are related to the process. The plus or minus signs of Q and W are: system endothermy Q>0, system exothermic Q0, and the environment does work on the system W