Chapter 107

It’s May 1st, Labor Day.

This year’s Labor Day can be described as ill-fated.

Because May Day happens to be stuck on Wednesday, a day that is neither up nor down.

Therefore, according to the original arrangement, Labor Day is only celebrated on May 1st.

However, fortunately, a certain journalist lady spoke up and the bosses above extended the May Day holiday to four days after discussion.

According to national regulations, there is a four-day holiday on May Day!

But according to the school regulations of Haicheng No. 1 Middle School, for senior high school graduates, they only have one day off on May Day.

Moreover, it is also the last chance for a vacation before the college entrance examination.

The next vacation will be after the college entrance examination.

According to the original words of the class teacher, Teacher Ma Qiumei, if you want a vacation and want to wander around, no problem, just stick to it for another month.

After one month, you have nearly three months off to do whatever you want.

Whether you want to sleep until you wake up naturally every day, stay up late playing games in an Internet cafe, or go on a spontaneous trip, no one will restrain you.

But in this last month, we must be strict with ourselves and not allow even the slightest bit of slack!

…………

May 1st is also the day when the 34th National Physics Competition for Middle School Students begins.

Su Xi is still on a business trip abroad.

As Su Ling's competition tutor, Gu Lu personally accompanied Su Ling to participate in the competition.

Like the mathematics league, the physics competition is also held nationwide, but examinations and awards are conducted in different provinces.

Different from the mathematics league, the physics competition not only has a written test part, but also an experimental part.

The same full score of three hundred points.

The written test is worth 200 points and the experiment is worth 100 points!

The written test papers are uniformly written nationwide.

Experimental topics are independently proposed by each province according to their own circumstances.

Generally speaking, the experimental questions are not difficult.

What is examined is the students' use and operation of physical experimental equipment, and not too much theoretical knowledge.

Therefore, as long as you make sufficient preparations in advance and have a clear understanding of the operation of all experimental equipment, it is not difficult to get a score of more than 90% in this link.

The difficult part is the written test.

Like the second test of the mathematics league, the written test of the physics competition does not have the option to fill in the blanks and is all big questions.

Moreover, there are eight major questions.

The direction of investigation covers mechanics, electromagnetism, optics, thermal science, and modern physics.

The difficulty of each question is more than one level higher than the difficulty of the questions in the college entrance examination physics test paper.

…………

Gu Lu and Su Ling arrived in Quancheng on the night of April 30th.

Looking for a hotel near the examination room, Gu Lu booked two rooms and settled in temporarily.

The next day, the 34th National Physics Competition for Middle School Students officially started.

In terms of the number of participants, the physics competition is naturally not as large as the mathematics league.

But in terms of the quality of candidates, it is not inferior to the National Middle School Mathematics League.

This year’s CPhO, more than 3,000 candidates from across the province participated.

The provincial team quota is only about five or six players each year.

Written test in the morning and lab in the afternoon.

Downstairs the teaching building used for exams, Gu Lu waved to Su Ling, who was about to enter the exam room.

"come on!"

"Yes!" Su Ling's little face tensed up, she clasped her little hands, and nodded heavily to Gu Lu.

Then he turned around and walked into the examination room with firm steps.

At nine o'clock, the written examination officially started.

Su Ling looked at the confident and upright figures sitting in the examination room with some anxiety.

Compared with those who were full of confidence, Su Ling was obviously a little less confident.

After all, Su Ling only had two months to prepare for CPhO.

The other candidates, at least during the winter vacation, have already started preparing for the CPhO.

Su Ling seemed to have forgotten all the bold words he had promised before.

At this time, Su Ling was like a little white rabbit that had slipped into a pack of wolves, huddled in a corner, shivering.

The exam start bell rang.

The invigilator distributes the test papers.

After receiving the test paper, classmate Su Ling felt a little uneasy and glanced at the eight questions on the test paper in sequence.

Hey! How could the first question be so easy?

Huh? Who else would ask such an easy question like the second question?

Ha?! I have done a similar question to the third question, but the data is different.

Humph, it’s just the fourth question, do you still think about me?

…………

Su Ling's big eyes gradually curved and narrowed into the shape of a crescent moon.

"It's very simple!" Su Ling murmured in a low voice with a sweet smile on her lips.

Just now, she was scaring herself.

Sure enough, just like what Teacher Gu said to him last night, as long as he can perform normally, he can pass this national physics competition for middle school students.

Then, next, it’s my turn to perform!

Su Ling took out a carbon pen from the pen bag, pulled off the pen cap, and paused the pen tip in mid-air, thinking about the solution to the problem.

The first question is a mechanics question.

It is also the easiest of the eight questions.

[A radius is R, the inner smooth hemisphere is fixed on the ground, and the opening is horizontal and upward. A small slider obtains the horizontal velocity along the spherical surface at the highest point on the inner side of the hemisphere, and its magnitude is v0 (v0≠0),

Find the maximum speed that the slider can reach during the entire movement. The acceleration due to gravity is g.]

Send points together!

Let alone a student of the Physical Education Examination, even if a high school student were to come over, there would be no problem at all in completing this question.

Su Ling shook her little head, writing formulas on the scratch paper while thinking rapidly.

"With the slider and the earth as the system, its mechanical energy is conserved during the entire movement. When the slider moves along the inside of the hemisphere, its speed v can be decomposed into a horizontal component vφ and a vertical component vθ."

"...Next, from the conservation of mechanical energy, we can get, 2mv0^2=-mgRsinθ1/2mvφ^21/2mvθ^2. Then according to the law of conservation of angular momentum, mv0R=mvφRcosθ."

"...To sum up, Vmax=vφ^2=1/2(v0^2v0^416g^2R^2)!"

First question, done!

Except for a few more formulas, it is not much different from ordinary high school physics questions.

This is the subjective feeling of classmate Su Ling.

The next question is about electromagnetism.

[The two plates of the parallel plate capacitor are located in the plane of z=±d/2, and the capacitor is not charged at first. The entire device is in a uniform magnetic field. The magnitude of the magnetic induction intensity is B, and the direction is along the negative direction of the x-axis, as shown in the figure.]

→_→Pretend there is a picture here

[1. Only the magnetic field exists in the capacitor reference frame S; and at a constant speed (0, v, 0) along the positive direction of the y-axis relative to the capacitor...]

[2. Now let the electrically neutral liquid (insulator) with dielectric constant e flow at a constant speed between the two plates of the parallel plate capacitor, with the flow speed v and the direction along the positive y-axis, in a reference system that is stationary relative to the liquid...

】

Simple, so simple that it’s outrageous, so simple that it’s hard to accept.

How can such a simple question reflect the difference between me and other candidates?

Amidst such continuous sighs, in less than two hours, Su Ling completed the answers to all eight questions.

…………
Chapter completed!