Tang Yan looked at Yun Yi seriously.

"Senior Brother Yunyi, do you know why the sky is blue? Why does paper turn yellow after a long time? Two stones of different weights fall from a height, which stone will land first? ”

Yun Yi was stunned for a while.

How many lifetimes have passed? It was the first time a question had been asked to him.

However, it's just because the question is relatively new, so I'll ask for the time being.

He looked up at the sky, took out a yellowed book from the storage ring, looked at it carefully, and finally picked it up from the ground, one large and one small, and checked it in his hand.

"The paper turns yellow, which is probably the reason for the invisible breath in the air. Yellowed paper is no longer the same as fresh paper, mixed with elements of the invisible qi in the air. ”

Tang Yan was immediately impressed by Yunyi, although the words were a little strange, but what he said was completely right, that is, the paper was oxidized by the oxygen in the air.

Yun Yi continued: "The question of these two stones is somewhat interesting. I subconsciously thought that the big rock would land first, but after thinking about it carefully, I found that the two should have landed at the same time, which is a bit magical. ”

Tang Yan was surprised again.

Although Yunyi didn't say why, the answer was right!

You must know that in Tang Yan's world, people mistakenly believe that the speed of falling objects is determined by the weight of the object itself, and the heavier the weight, the faster it will fall. This misconception has persisted for nearly 2,000 years.

It wasn't until the advent of Galileo and the famous Leaning Tower of Pisa experiment that everyone knew that the speed at which an object fell had nothing to do with its own weight.

I didn't expect Yunyi to have an experimental spirit.

Tang Yan praised: "That's right! I thought you'd be fooled for thinking that the heavy stone would fall fast. ”

Yun Yi shook his head with a smile: "No need to praise, it's just a very simple truth." Two stones, one large and one small, if the big stone falls fast, the small stone falls slowly. That tied them both up, and the speed should be in the middle. But when the two are tied together, the weight will become larger, and according to the principle that heavy things fall faster, they should fall faster when they are tied together. Therefore, the two theories contradict each other, as long as you think about it, there will be no misunderstanding. ”

Yunyi said it simply, but if it were that simple, people wouldn't have misunderstood it for nearly 2,000 years.

Tang Yan gave Yun Yi a thumbs up: "What about the first question I asked?" Why is the sky blue? ”

"I subconsciously thought that the sky itself was blue. But then I thought about it, flying in the sky, you can't see the sky entity at all. So I'm also thinking, if the unreachable sky, if it's really blue, how can we see so far? Yun Yi fell into deep thought.

Tang Yanxin said good guy!

She wanted to talk about the scattering of sunlight by the atmosphere. Only blue indigo violet light is scattered by particles in the atmosphere due to its short wavelength, and blue light has the largest energy, causing people to perceive the sky as blue.

But as Yun Yi said, it is no longer enough for light to explain the scattering of sunlight. It's time to explain that the Earth is round, and what happens to galaxies!

However, the more complicated the other person's thoughts, the easier it is to arouse interest, which is a good thing.

Tang Yan hooked the corners of his lips slightly: "Then Senior Brother Yunyi thinks, what kind of invisible qi makes the paper yellow?" Since the falling speed of an object is not affected by weight, what is the effect? Why can you see colors when you can't touch the sky? ”

"Why?" Yun Yi thought about it and asked Tang Yan, "Does Senior Sister know the answer?" ”

Tang Yan nodded: "This is also written in the book I found in the library of the palace. But what is the specific reason, I'll sell it first, senior brother think about it slowly. ”

After saying this, Tang Yan turned around and left, leaving Yunyi to study alone.

In the next few days, Tang Yan never mentioned the previous question. I want Yunyi to be interested in nature and science in the process of inquiry.

Under the leadership of Zhou Jingru, several people finally arrived at the territory of the Qingqiu Fox Clan.

The patriarch is an old fox in the late stage of foundation building, and greeted Zhou Jingru and the three of them warmly and respectfully, and also compiled the lost portraits of the clansmen and basic information into a book and handed them to Zhou Jingru.

Tang Yan is comparing endurance with Yunyi unilaterally these days, to see who speaks first.

It's just that the other party not only didn't mean to speak, but he didn't even frown these days.

Could it be that you didn't think about it?

There are still no long offset points.

Tang Yan felt that compared with the other party, it was probably himself who couldn't hold his breath in the end.

After Zhou Jingru got the portrait and information, he asked Tang Yan.

"I see that there are a lot of little foxes here, junior sister wants to stay here for a while?"

How could Tang Yan be in the mood to play fox?

Besides, many little foxes who have not opened their minds or have just been in the Qi refining period still retain the nature of beasts, and pee in the open air, and they are smelly and stinky, which is not cute at all.

Tang Yan waved his hand: "Let's go, let's go find the lost fox." ”

The group of three left Qingqiu and walked all the way to the palace.

Qingqiu County is not close to Kyoto, and you can look for the fox demon on the road.

Along the way, Yunyi followed very obediently and did not express his opinions at all.

After waiting for two days, Tang Yan felt that he had lost, so he had to take the initiative to ask the other party.

"The previous three questions, did Senior Brother Yunyi figure it out?"

Yun Yi looked at Tang Yan, nodded, and shook his head again.

With a wave of his right hand, he separated the oxygen from the air: "It should be this invisible gas that causes the paper to turn yellow." ”

Then he pointed to the ground under his feet: "I have traveled many places over the years, and the ground under our feet should be spherical. The reason why the person standing under the sphere did not fall is probably because there is some kind of attraction in the heart of the earth. I think the speed at which an object falls should have something to do with this attraction. It should also be related to the direction of the wind at that time, as well as the obstruction of the wind to the object. ”

Tang Yan didn't know what to say in his heart except for.

Don't look at the fact that people have not systematically studied physical chemistry knowledge, nor have they thought about it. But after all, after living for tens of millions of years, the knowledge is really not comparable to ordinary people!

Zhou Jingru laughed out loud on the side: "Senior Brother Yunyi, how old are you, you dare to say that you have traveled a lot?" Although there are mountains and ravines in our Cangqing Continent, it is still a smooth road on the whole, and it is absolutely impossible to be spherical! ”

Yun Yi smiled and did not speak, nor did he refute, but listened to the lecture with an open mind.

Tang Yan couldn't wait to ask: "The first two books are almost written like this. And what about the answer to the last question? ”

Zhou Jingru was a little curious on the side: "What's the problem?" ”

Tang Yan replied, "Why is the sky blue? ”

Zhou Jingru suddenly laughed: "What kind of problem is this!" Because the ground of the heavenly immortals is blue, our sky is blue. You see, the ground under our feet is black, and the legendary hell, isn't the sky black! ”

Tang Yan: "......"

Boy!

The continent of the flat plate, there are three mezzanines, is this a sandwich!