I Just Want to Be a Quiet Top Student

Z=4

Z represents the nuclear charge of an element.

Which element in the periodic table has a nuclear charge of 4?

Hydrogen helium lithium beryllium boron, carbon nitrogen oxygen fluorine neon...

Obviously, beryllium has a nuclear charge number of 4.

This question explains a phenomenon through a bunch of symbols, mathematical operations and physical principles, that is, Be2+ ions are captured during the recombination process of gas discharge.

After a series of derivations and calculations for this calculation problem, Shen Qi finally gave the answer: Z=4, which is beryllium element.

From macroscopic mirages to microscopic ion capture, most phenomena in the world can be explained by mathematical and physical methods. This is the beauty and power of science.

Of course, there are also supernatural phenomena that human scientists cannot explain. Let non-humans above level 15 solve these problems.

It took Shen Qi an hour to complete the first two questions.

The first two questions are indeed difficult, and it's not that the top students can't handle them.

This semi-final exam paper is also naughty, the first two questions are difficult, but the latter big questions are not too difficult.

20 points for the third question, 24 points for the fourth question, 20 points for the fifth question, 22 points for the sixth question, and 20 points for the seventh question.

Shen Qi spent another hour to finish the five calculation problems in the middle.

At this time, two hours had passed, and Shen Qi had completed seven of the eight questions in the rematch theory test.

The last calculation question has a score of 26 points, the highest score in the whole paper.

"Damn it?" Shen Qi tried the question three times in a row, "The big axis question is so simple? Give points? Or die for pretending to give away points?"

The stem of the last question is:

"Let there be 4/5 nitrogen molecules and 1/5 oxygen molecules in the air."

"The temperature near the ground is 27°C and the pressure is 1 atm."

"There is a spherical artificial satellite with a cross-sectional area of ​​1 square meter at a height of 10 kilometers above the ground, which moves around the earth at an initial velocity."

"If there is no atmospheric resistance, the initial velocity of the satellite is just enough to make it orbit the earth in a circle."

"However, atmospheric drag exists."

"Try atmospheric resistance."

After Shen Qi reviewed the questions three times, he tried again three times.

hehe.

Dregs.

Don't think that if you wear a noble and gorgeous coat with 26 points, I won't dare to mess with you.

Shen Qi was finally sure that the big axis question with the highest score was nothing more than a paper tiger.

Launching satellites is a physical phenomenon combining mechanics and heat.

Because the atmosphere rises slowly, it can be regarded as the troposphere for static treatment, where there is a differential relationship in which the pressure formed by atmospheric gravity decreases with height.

The ratio of nitrogen molecules and oxygen molecules set in the question came in handy.

As the altitude rises, the atmosphere expands adiabatically, and the equation of temperature and pressure can be obtained.

With the help of mechanics knowledge, it is not difficult to estimate the initial velocity of satellite movement, which is close to the first cosmic velocity of 7.92km/s.

The collision between the satellite and the atmospheric molecules can be approximated as the elastic collision between the circular sections of the satellite perpendicular to the flying direction of the atmospheric molecules.

Therefore, Shen Qi quickly calculated the result, the atmospheric resistance suffered by the satellite is:

F=5.5×10^7N

The eight questions in the semi-final theoretical exam were related to optics, quantum theory, electricity, electromagnetism, mechanics, acoustics, preliminary astrophysics, and heat. The teacher who wrote the questions described the mortal world through the test paper.

"The teacher who made the question regards himself as a god." Shen Qi checked the test paper once, and then checked it again.

Although there were still 30 minutes left, Shen Qi was not in a hurry to hand in the paper, checked, and continued to check, spending the three hours of answering all the time.

"If I don't get 160 in the test, how can I face my ancestor Shen Gong?"

160 is the full score for the theoretical test paper in the semi-finals, and Shen Qi devoted all his strength to this test paper, aiming to get 160 for sure.

After the game, Mu Rong gathered the 13 players who participated in the rematch to understand the situation.

"It's hard!" Bai Lingye yelled that my life is over.

"It's quite difficult." Lin Xingyu looked serious.

"There is a certain degree of difficulty." Shen Qi told the truth.

"Shen Qi, you didn't hand in the paper in advance this time." Mu Rong felt that the situation was not optimistic.

"The first two questions are indeed a bit complicated." Shen Qi said.

"Hey, I didn't write the fill-in-the-blank question, and I can't deduce the trajectory equation. This question obviously touched the blind spot of my knowledge. The quantum theory of the second question is more abnormal, and I wrote it blindly. The satellite question of the last question is calculated as atmospheric resistance. , I clearly have an impression, but I am confused as soon as I take the exam, I am a worthless salted fish." Bai Lingye said bitterly.

"Actually, what Teacher Mu said was that we didn't learn well." Lin Xingyu looked for problems from himself.

"I may not get 80 points in the theory test with 160 points. Forget it, I don't need to take the test questions, and it's useless." Bai Lingye said dejectedly, advancing to the national finals and winning the national award , entered the physics experiment class of Yanda University, and was finally left by Yanda University... This is too difficult to do. Bai Lingye is also considered a primary school bully in their class. It's no different from a scumbag.

"Remember students, never give up hope!" As the leader, Mu Rong had to be optimistic, although she was a little pessimistic.

Nearly a thousand contestants from the whole province participated in the semi-finals. According to the practice of Southern Guangdong Province, no more than 10 people were finally selected to represent the province to participate in the national finals. Because the experimental questions have not yet been tested, Shen Qi is not 100% sure that he can do it right now. In the national competition, he comforted the two juniors: "Lin Xingyu, Bai Lingye, you are only sophomores in high school, you still have a chance next year. Teacher Mu is right, never give up hope, even this year, don't give up hope, don't give up hope Talent is a salty fish, at least we can still fight on the experimental questions."

"Yeah!" Lin Xingyu nodded heavily, stubbornly letting himself hold on to a glimmer of hope and not let go.

"Okay, everyone has worked hard, go back and have a good rest, adjust your status, and disband." Mu Rong issued the disbandment order, and everyone went back to their respective homes.

94% of the contestants in the preliminary round were eliminated, and the number of remaining contestants dropped sharply. The grading of theoretical test papers for the CPhO rematch progressed very quickly.

One day later, all contestants in the semi-finals will be able to self-check the theoretical test results of the semi-finals on the China Physics Competition website.

Shen Qi used his mobile phone to check his score, feeling a little uneasy.

Enter the test number and click "Query".

The mobile phone scoring system shows:

Name: Shen Qi

School: Nangang No.2 Middle School

Exam number: 10201XXX

CPhO semi-final theory test score: 159

After seeing the score of 159, Shen Qi was shocked: "Who... who the hell is embarrassing me? Why did you deduct one step point from me?"

Full marks for this kind of thing, if you don't taste it, you will be addicted once you taste it, just like smoking opium.

No one can accept the cruel reality of getting two "full marks minus one point" in the CPhO preliminaries and semi-finals.

"So, even if I get a full score of 40 on the experimental questions, the total score in the rematch is at most 199 points. I... I may not be able to enter the national final." Shen Qi felt the pressure.

"Brother, you are thinking of a master of learning, oh no, of thinking of a god of learning. You have a score of 99 in the exam for a master of learning, and you have a long-term perfect score of a god of learning. However, there are several gods of learning in the province, and the score of 159 in the theory test is very high. ! Do you think everyone can get full marks in the test?" Lin Xingyu's theoretical test score was 130, which he was quite satisfied with, already exceeding his expectations.