"What the hell is the old man studying?" Qin Feng asked out loud.

Huoyuan rubbed his chin and replied lightly: "I heard that the old man accidentally mentioned it after he was drunk, and he wanted to build a city that could be moved. ”

Qin Feng's eyes widened, Harvey's mobile castle?

I didn't expect this old man's idea to be so avant-garde!

It is worthy of being a man who can forge the supreme twelve soldiers and build the Flying Court and the Empty Courtyard.

"But if you want to build a city that can move, why did the old man come up with something that looks like a cart.

Do you also have to push objects of various shapes and materials around on the ground? Qin Feng raised his doubts again.

"The old man's original idea was to build the city on a chariot, like a horse-drawn carriage pulling goods, and through the power of treasures, the entire city was affected.

The weight of the city must be extraordinary, so when the old man tried it, he would place goods far more than the carrying weight on the car.

However, the result is that the car can easily slip and roll over, and if it encounters soft soil, the wheels will become stuck in it and cannot move.

The old man suspected that it was a problem with the shape of the wheel, so he wanted to improve it. Hiragaki explained.

Qin Feng nodded, thinking in his heart: "No wonder the patriarch has been rubbing back and forth on the ground with various objects, it turns out that he wants to find the most suitable wheel. ”

However, the old man tried for a long time, but found that the wheels, which did not sink into the mud, could not pull the goods.

The wheels that can pull the goods are very prone to slipping and rolling over and falling into the mud.

Therefore, even if the old man spent a lot of things on this matter, there was no progress. Huoyuan sighed, his tone a little regretful.

The city that can move is simply a man's romance, and as a member of the Divine Workshop, he naturally has a great desire for such novelties.

But who would have thought that this world-class research would not even take the first step.

"Hiss~" Qin Feng scratched his cheeks, thoughtful.

Although the old man is ingenious and has new ideas in his head, the shackles of the times will inevitably lead to many restrictions on the old man's ideas.

"Wait, if I can help the old man solve this initial problem, can I use this in exchange for him to help forge knives by making an exception?" Qin Feng's eyes lit up slightly.

After thinking about it for a moment, his face became a little ugly again.

"This kind of thing must involve physics-related knowledge, I'm a man who applies for liberal arts for the sake of many girls, where do I know this."

The corners of Qin Feng's mouth twitched, his level of physics knowledge was still in high school.

"The high school science teacher didn't lie to me, I learned mathematics, physics and chemistry well, and I was not afraid to go all over the world.

Blame me for being too young and dismissive of it......

But fortunately, because what I learned was Wensheng Taoism, I remember the physics knowledge in high school very clearly.

I don't know if this shallow knowledge is enough. ”

"Actually, I don't need to give the old man an answer, I just need to provide him with an idea.

Wheels, moving, sinking into the dirt...... It should involve knowledge such as friction and pressure.

Hey? I seem to have an idea. Qin Feng raised his eyebrows, raised his steps, and approached the old man again.

Huoyuan stretched out his hand, and just as he was about to stop it, a heavy bag of money fell into his hand.

When the words came to his mouth, he swallowed them back again.

When the patriarch heard the footsteps approaching, his brows furrowed, and he scolded bitterly: "That little rabbit cub." ”

The people in the Shen Workshop are short of money, which is well known in Daqian.

The little rabbits used him as an excuse to sell information to obtain money, both of which were privately agreed upon.

The old man naturally knew about this for a long time, but he has always chosen to turn a blind eye.

It's just that he didn't expect that this kid who came today would be so rich and stubborn.

"Boy, if you still ask me to forge a knife, die of this heart as soon as possible, don't waste your efforts." The old man's attitude is still firm, and his tone is irrefutable.

To his surprise, this time the boy in black did not mention the forging of knives, but asked inexplicably: "Old man, do you know what friction is?" ”

The patriarch frowned, not knowing why.

Qin Feng coughed dryly, and regardless of the other party's reaction, he directly memorized the knowledge in the high school physics textbook-

"Well, the so-called friction force refers to two objects that are in contact with each other and squeezed, when they are in relative motion or have a relative motion tendency, the force that hinders the relative motion or its tendency is generated on the contact surface, which is called friction.

Haven't you wondered, old man, why the wheels of the carriage are round instead of square, or other shapes?

Why is it that a wine glass can be easily pushed on a smooth tabletop and is difficult to move on a rough floor?

Why does the old sow ...... in the middle of the night"

At this point, Qin Feng stopped abruptly.

I almost said it in passing......

The patriarch originally planned to drink Qin Feng back, but when he heard this theory, a certain string in his head seemed to twitch.

He thought for a moment, and then his eyes widened: "According to your theory of friction, the reason why the wheels are all made round is because when they roll, they have less contact with the ground.

Thus reducing your so-called friction? ”

Awesome, you can get to the point so quickly...... Qin Feng was surprised in his heart, but nodded slightly, revealing the appearance of a teachable child.

"Why is it that the same wine glass, which can be easily pushed flat on a smooth table, but not on a rough floor?

Its contact area is all the same. The senator was quick to ask questions.

Hooked...... Qin Feng smiled meaningfully and said lightly: "This involves the concept of a coefficient of friction. ”

......

The group of people waiting for the Divine Workshop in Huoyuan not far away originally thought that Qin Feng would be driven back soon.

But the development of things surprised them.

The old man, who doesn't smile on weekdays, is discussing with the handsome man in black, what is he talking about?

Even dancing with excitement?

"What's the situation?" Gongliang, who sensed the abnormality, stepped aside and asked curiously.

"I don't know, go over and see?" Huoyuan glanced at it.

"Let's go."

The rest of the people from the Divine Workshop glanced at each other, and followed the two bosses in a hurry.

Only the three Blue Frost were left in place.

"What are Brother Qin talking to the patriarch? It's the first time I've seen that old man so excited. Yang He's face was incredible.

Zhang Tiannan nodded, although he didn't speak, his eyes were also full of curiosity.

And it didn't take long for the group of people in the Divine Workshop to change.

They either frowned in thought, or showed a look of joy that suddenly dawned on them.

The sound of inhalation and exclamation came and went.

The three of Lan Ningshuang, who could no longer suppress their curiosity, hurriedly approached ......