Yan Yunzhou sat next to Ning Qi, and looked at the things drawn on his desk, he had been watching Ning Qi write and draw here in the past few days, thinking that he was still working on those things before, thinking that the paper was still some "chemical formula" that Ning Ji had said, but this time there was no "symbol" on the paper that he was familiar with.

And it's all lines? Horizontal, vertical, and arc? He asked with some curiosity:

"What is this drawing?"

Ning Yi put down the pen, and the whole person collapsed on the seat like a big character, and took a snack sent by Yan Yunzhou in his hand and stuffed it into his mouth:

"I wondered what the hell was I doing here? Is it to take the college entrance examination again? ”

Yan Yunzhou picked up the paper on the table, he didn't understand the things drawn on it, but it looked like it was a path thrown out? Is this the parabola that Ning is talking about?

"Is this arc the route of gunpowder throwing? What do these symbols mean? ”

Ning Ji ate the snack clean, and pointed to a few formulas and symbols on it:

"This is the x-axis, this is called the y-axis, this Vx represents the speed in the horizontal direction, and Vy represents the speed in the vertical direction, so I won't explain more to you, I can roughly calculate how many meters the horizontal face of the center of the river will be advanced, and then set up a high platform to project ammunition It is possible to hit the opposite side."

Yan Yunzhou's gaze could not hide his shock:

"Can you just draw it out with just one drawing?"

Ning Yi was amused by his "uneducated" appearance, supported the armrest on the side with his hand, and said with a smile:

"That's nature, and although my physics is far less solid than what I remember about chemistry, it's not hard to figure it out."

Yan Yunzhou looked at his smug expression like a little squirrel, and ruthlessly dismantled the stage:

"It's not difficult, then you're about to scratch your head."

Rather...

The author has something to say:

Others have crossed over to reach the pinnacle of life, and Director Ning is to learn mathematics, physics and chemistry again

Don't give up if you're still studying, once you cross over, you're the king

Chapter 101: Gunpowder is now seriously injured

During this period of time, Yan Yunzhou and Ning Qi can be regarded as getting together less and leaving more, even if they are also in the military camp, there is very little time for the two of them to meet.

This time it was rare to be idle, Yan Yunzhou really didn't worry too much about the things in the barracks, everything that could be handed over to Li Yan was handed over to Li Yan, and he stayed by Ning Yan's side almost all day.

Ning Qi was writing and painting behind the table, Yan Yunzhou leaned on the soft couch by the window and closed his eyes to recuperate, the window was open, and the slightly warm wind blew in in May, which was extremely comfortable.

Ning Ji raised his head and could see the man's handsome outline, his usual pale complexion was reflected in the sunlight through the window, his face looked much better, and his long eyelashes cast a shadow in the sun.

It's just that the person's breathing is still a little heavy, and he coughs from time to time, and if you look closely, the rise and fall of the person's chest is more obvious, and Ning Blame walked over.

Yan Yunzhou didn't open his eyes when he heard his footsteps, but when Ning Qi was standing beside him, he suddenly stretched out his hand and accurately clasped his wrist, Ning Qi was swept away by his strength, and his whole body rushed forward uncontrollably.

He was startled for fear of smashing the person below, and the next moment Yan Yunzhou's hand held his shoulder and hugged the person in his arms, Ning Qi looked up and saw the person's face poking at the smile:

"What kind of surprise attack? I thought you were asleep. ”

Ning Yi wanted to get up from him, but Yan Yunzhou didn't let him go:

"It's been sitting all morning, are you done?"

Ning blamed him and squeezed into a recliner:

"Almost, by the way, I want to build a lookout by the river, how high can I build?"

"Lookout?"

"Well, come and see."

Ning Qi helped Yan Yunzhou to get up, pulled him directly to the back of the table, pressed the person to sit on the chair, and put the picture he drew in the morning in front of him:

"Admire it."

Yan Yunzhou looked down and saw that the drawing was not a specific figure, but a line similar to yesterday, and knew that this must be something that Ning himself could understand, and smiled:

"Explain it to me, I don't understand."

Ning Ji came to him and sat down, he looked at Yan Yunzhou's incomprehensible appearance and felt a little cute, he took a pen:

"Look at this arc, this horizontal line is the lateral displacement, and the vertical line is the vertical height, I want to build a lookout, and then set up the cannon on the lookout."

Yan Yunzhou looked down at the map and listened to him, looking at the arc in the map, he also picked up the pen and directly drew the topographic map of the outside of Zhangzhou City and the Fen River on the map, and the map of these places had already been imprinted in his mind:

"Can you figure out on the map where the cannon erected by the lookout can go farther?"

Ning Yi smiled:

"I'm really a connoisseur, ask the most important question as soon as you ask, you see that this arc is actually the path of artillery fire.

What we need to figure out now is how much this lateral displacement can reach, but no matter how it is calculated, it is certainly impossible to hit the other side, but there should be no problem in hitting the middle of the river. ”

Ning was born in medicine, and his familiarity with chemistry was naturally much stronger than that of high school physics, and he thought about it all night before he deduced the calculation method of the flat throwing motion he learned in school.

Flat throwing motion is actually a uniform variable speed curve motion, which can be decomposed into two kinds of motion, that is, a uniform linear motion in the horizontal direction and a free fall motion in the vertical direction.

All he needs now is how to lengthen the lateral displacement of the horizontal axis as much as possible.

He calculated the formula for half a day to pick up a little bit of high school physics knowledge, and according to the lateral displacement S=VT, it can be concluded that the lateral displacement is only related to the initial velocity and landing time.

And the initial velocity of the level is determined by the moment when the cannon fire is discharged, and he can hardly change it, and the only thing he can change is the landing time.

In fact, when the artillery fire is shot out, it is mainly affected by gravity, and the free fall movement in the vertical direction is positively correlated with the height and landing time, the higher the altitude, the longer the landing time, Ning blamed Yan Yunzhou said:

"Now I need to test the initial velocity of the artillery fire, and then determine the height of the watchtower and the position of the river according to this."

Yan Yunzhou listened to what he said, but there was one thing that he understood, that is, the higher the watchtower, the farther the artillery fire would shoot, which was also in line with the common sense of their cognition.

He took the pen from Ning Qi's hand, and Ning Qi watched him draw on the paper, the lines were clear, the structure was clear, this was painting the lookout?

"This kind of lookout is commonly used in the military, and although it is a bit troublesome to build, the height is the highest height that can be reached now, and it should be about fifteen meters."

Ning Qi immediately calculated, the height was fifteen meters, and according to the formula of free fall, it would take 1.73s for the artillery fire to land.

This time is really not long, and what we need to know now is how fast their crude cannon can reach at the moment when the cannon fire is discharged.

In the afternoon, Ning Qi asked people to pull a cannon outside the city, and Yan Yunzhou was not at ease:

"I'll go with you."

Ning Qi listened to his cough and still didn't get better:

"I'll be soon, you wait for me at home, it's windy outside today, and I just had a fever a few days ago."

Yan Yunzhou pulled his hand, and only lowered his head and spoke:

"The last time you tested TNT, you took Zou Xiaohu, and now you think I'm useless?"

Ning Ji looked at the person in front of him who was going through the old accounts with him for the first time, and felt that the old fox had a lot of eyes, if he didn't agree, maybe it would rise to a profound problem of disliking him or not disliking him:

"You're really good at talking, so don't ride a horse, go over on a carriage."

After a cup of tea, Yan Yunzhou leaned against the frame, it was after lunch, he was a little in good spirits, the frame was not fast, he leaned on the wall of the carriage and was a little drowsy.

Ning Ji looked at him and still couldn't hide his distress and helplessness in his heart, the medical treatment in this era was still too backward, he knew the pain of this person, but he was still helpless.

He raised his hand to replace the hand stove on the man's lap, which was already a little cold, and the person who had been sleeping untruthfully suddenly woke up, and Ning Ji helped him pull the blanket up:

"If you're sleepy, just sleep for a while, and you'll be there for a while."

Yan Yunzhou took his hand and led the person to his side, and Ning Yi also sat beside him according to his strength:

"What's wrong?"

Yan Yunzhou rested his head on Ning Qi's shoulder with a few fragile feelings:

"I don't know when this battle will end, Yu'an, if my health is worse than it is now in the future, will you dislike it?"

Yan Yunzhou, who had rarely seen such a look, was just about to speak out in distress, when he heard this person say again:

"After all, there is no filial son in front of the bed of a long-term illness."

One sentence knocked out all the soft hearts of Ning Fangcai:

"I treat you as a partner, but you want to be my father? Why? After you die, you still want me to dress you in linen and filial piety?

Don't useless hearts, are you a doctor or am I a doctor? I still don't know what kind of body you have, and I will dislike it a long time ago. ”

Yan Yunzhou didn't get up, his hand wrapped around Ning Qi's waist, the strength was not small, Ning Qi smiled, let him hug him, he could actually feel the uneasiness in Yan Yunzhou's heart, empathy, if he was such a body, he might not have such worries:

"Okay, my lord, I don't dislike it, I don't dislike it now, I won't dislike it in the future, we can go, we can't go, I'll build you a wheelchair, what's it?"

Throughout the afternoon, Ning Qi led a team of men and horses to test the distance that the cannon fire could shoot, and he silently counted the seconds in his mind so that he could roughly calculate the initial velocity of the gunpowder discharge.

In the end, the approximate velocity was about 150 m/s, which was more than twice the speed of a bow and arrow, but it could not be compared to modern artillery fire.

After all, Ning Qi studied medicine, which made him not have a very accurate understanding of the speed itself and the width of the river in his heart.

According to the initial velocity of 150m/s, 1.73 seconds, the lateral displacement can reach 259.5 meters, he didn't have much concept of this distance itself, but when this result was brought to Yan Yunzhou, the person's face changed:

"Yu'an, are you sure this is not a mistake?"

"No, even if there is an error, the result will not be a few meters off, what's wrong? Is this a good result? ”

Yan Yunzhou looked at him and smiled:

"This section of the Fen River is considered wide, but the width should not be 300 meters, if you are okay with this, this artillery fire is on the lookout platform of fifteen meters, and it is almost able to hit the opposite side."

This answer made Ning Ji stunned for a moment:

"Really? Wouldn't we have to endure until winter? ”

When he went back that afternoon, Yan Yunzhou took Ning Yi directly to the big tent, and took out all the drawings and the data of this afternoon's test.

Yan Yunzhou looked at Ning Qi:

"Come on."

Ning Qi nodded, and hung up the drawing, in addition to the topographic map of the river that he drew and Yan Yunzhou supplemented, it would look more intuitive, and after he said his thoughts, Li Yan's eyes widened:

"Erecting a fifteen-meter high platform, can the artillery really hit so far?"

"Theoretically, that's true."

"Brother Yan, can the high platform be erected to fifteen meters?"