Xueba, I beg you to go and escort him quickly!

I was chatting in the group!

withdraw!

Withdraw immediately!

But they all saw it.

The group leader, "[crying expression] Mrs. Xu Heng took care of the feelings of us scumbags! Touched!"

Rainbow farts, one after another!

"[Crying expression] [Crying expression] [Crying expression] Xu Heng is so considerate! I want to give birth to a monkey for you!"

"Bah! Shameless, I'm the first one to give birth, it's not your turn!"

"..."

Xu Heng, "%￥#%..."

Forget it, or quit, stop watching it!

After washing up, Xu Heng went to class, ate a delicious breakfast, then took out the blanket, and continued to lie comfortably on his stomach.

He doesn't play games anymore!

There is nothing to chase after dramas!

Hey……

boring!

Looking at Yang Kaixuan again, he didn't know how many books he had changed.

Swish, swish, full of energy.

Xu Heng looked at this kind of information and that kind of information on his desk, and then looked at the clean and tidy desktop in front of him.

The gap is not a little bit big!

And Yang Kaixuan had already taken a comparison picture of Xu Heng's desktop and his desktop before.

Now there is still a circle of friends!

It was Yang Kaixuan's emotion.

Xu Heng swiped his phone.

At first glance, the one on the left is very messy, all kinds of test papers act as scraps of paper and information books!

Look at the right side again, it is very tidy, and some books are still new!

Xu Heng approached Yang Kaixuan, "What do you want to express?"

Yang Kaixuan's copywriting is: Do you guess that is Xueshen [crying expression]? !

Yang Kaixuan blushed, "Ah..."

"To be honest, all the comments in my circle of friends think I'm Versailles!"

"It's been said that it's not easy to learn a god, all kinds of things... and they say that you are a scumbag in your position..."

"Hey!"

"I just want to sigh, no matter how hard I try, I'm not as good as you, but those people in the circle of friends have misunderstood it!"

"I'll send another one!"

Xu Heng, "???"

Within 2 minutes, Xu Heng refreshed his circle of friends.

It is Yang Kaixuan's latest circle of friends:

"I, frantically brushing the questions, one small material for two days, one big material for three days, I know all the example questions and knowledge points in the textbook, which page, which line!"

"Learning at the same table as a god, watching dramas crazily, a 30-episode TV series in two days, and a 50-episode TV series in three days. "

"Hey! The difference!"

He didn't say it directly, but expressed emotion like this.

Xu Heng, "Eh...Yang Kaixuan, how did you become a joker?"

Yang Kaixuan, "Pfft, you're the joker!"

"I'm just stating the facts! Can you say that you are not in a drama shortage now? Otherwise, you wouldn't be bored to come to me!"

Xu Heng, "Uh..."

I didn't expect to be seen through!

Yang Kaixuan grumbled, "My girlfriend doesn't bother me, you bother me, Xu Heng, what's your intention!"

Xu Heng, "Uh..."

Yang Kaixuan, "Xu Heng, if you are really bored, go talk to those recommended students in the group to talk about retirement life!"

"Otherwise, you let them find some problems for you to do?"

"After all, there are more people and more power!"

"Let's talk about it! There are still a few seniors from Peking University in the group! Would you like to communicate with them?"

After Xu Heng thought about it, this was a good choice.

In the group, I found one of the three physics department seniors named Wang Hanshan.

"Hello, Senior Wang!"

Wang Hanshan has no class in the morning, but he has already gone to the study room in the library early.

The phone rang suddenly, Wang Hanshan picked it up and looked at it, and was instantly stunned.

The other two students who came to the library to study with him were also curious when they saw him stunned, and asked in a low voice, "What's wrong?"

This is the library self-study room. Although it is very early, there are still many students there, so their voices should not be loud enough to affect other students.

Wang Hanshan looked at the two roommates in front of him, "Xu Heng sent me a message!"

These two, "!!!"

"Could it be that you have encountered some difficulties? Are there any problems that you can't solve?"

"Quickly ask, he doesn't know that question, let's help him!"

"It seems that this classmate Xu Heng is not omnipotent!"

"Maybe student Xu Heng has encountered that question before, so that's why he came up with it!"

Wang Hanshan, "Maybe! I also solved this problem, but it took longer than his time..."

"As for him being able to figure out this problem in a short time, I think he must have encountered a similar problem, otherwise, it wouldn't make sense at all."

The other two nodded frequently.

"When I first heard about it, it was indeed unbelievable."

Wang Hanshan smiled, "But after looking back, calm down and think about it again, it is his skill to have such a question in his question bank! I have to admit it."

"Yes!" The two looked at each other.

"So, ask classmate Xu Heng, what do you want us to do?"

Wang Hanshan, "What's the matter? Student Xu Heng?"

Although they didn't say whether they wanted to ask questions that we didn't know, they all thought so in their hearts.

Xu Heng, "Do you have any questions?"

"You all know... some real questions in schools can't be found on the Internet, and the ones that can be found are all very simple, that is, the kind that are not easy to answer. I want to find some questions to pass the time."

What Xu Heng said was already very euphemistic.

When Xu Heng replied, Wang Hanshan was stunned again, the corners of his eyes twitching.

These two people, "???"

"what happened?"

Come and have a look!

Read every word!

"Wow...! Woohoo!"

He couldn't hold it back for a while, and almost yelled, but fortunately another one covered his mouth, and then it stopped abruptly.

The students studying around gave this side a hard look!

This is a self-study room, and it needs to be absolutely quiet. What are the three of you arguing about here this early in the morning?

"Calm down! Be calm!"

Only then did he let go, and the man took a deep breath, "Hoo hoo..."

"What does Xu Heng mean? Did he ask us to find questions? Did he ask if there were any questions we didn't know? Is that what he meant?"

"Good! Good! I really have a question! Give it to him!"

They thought Xu Heng did it on purpose!

So they are angry!

Started to get angry with Xu Heng.

Wang Hanshan saw the question, "Are you sure? This question was left by the professor last class, are you sure you want to give it to him?"

The two were aggrieved and nodded seriously.

"Fine!"

Without a word of nonsense, I just took pictures and sent them over.

Xu Heng was overjoyed.

"Seniors, you are indeed seniors! Thank you!"

Xu Heng's gratitude is that they feel that they have seen the big world and don't think too much about it!

But how did he know that the three of them are playing with Xu Heng!

"!!!"

"So defiant! This guy."

But Xu Heng didn't care about that much.

I looked at the topic with relish:

Imagine a lightweight elevator extending perpendicular to the ground to space in the plane of the earth's equator. The top of the elevator can exceed the height R of the earth's synchronous satellite (calculated from the center of the earth) and extend to the depth of space.

This so-called sky elevator can be used to launch satellites orbiting the Earth at low cost. The launch method is to lift the satellite to a certain altitude at a constant speed through a space elevator, and then activate the propulsion device to launch the satellite from the space elevator.

1. During a certain launch, the satellite ascends at a very slow and constant speed in the space elevator, and the satellite accidentally separates from the space elevator at the horizontal knife R (the speed of the satellite relative to the departure point on the space elevator during separation can be regarded as zero ) into space.

① Demonstrate that the satellite will not hit the ground after falling off

②If the satellite can meet the space elevator again after falling off, the satellite can be recovered when they meet.Discuss the possibility that the satellite will be recovered by the space elevator within two time periods of 0-12 hours and 12-24 hours from the moment of falling off.

2...

As for the second major question, they didn't shoot all of them.

Xu Heng frowned slightly, but then he was relieved.

"This should be asked for me!"

But in fact, the thinking of Wang Hanshan and the three of them was: the first question is enough for him to be busy for a long time, and as for the rest, don't even think about it.

Wang Hanshan whispered to the two, "Learn from yourself, this question alone is enough for Xu Heng to toss about!"

"Uh-huh!"

Several people have just entered the learning state.

"Om..."

Wang Hanshan's cell phone vibrated.