The entrance to the back door of Physics Laboratory No. 1 in the experimental building.
Shen Qi stood outside the back door, secretly observing through the glass recessed into the door.
Inside the physics lab, portraits of scientists such as Newton, Kepler, Faraday, and Watt hang on the walls, and four large characters are prominently displayed above the blackboard. "Unity of Knowledge and Action."
The laboratory layout differs from the classrooms in the teaching building. Desks have been replaced by long experimental tables, with a dozen or so students sitting behind them. Each table is equipped with various instruments and props, such as balances, vernier calipers, small balls, collision experiment equipment, timers, and weights.
But no one operated any of the experimental equipment. The students, some with their chins in their hands, others with furrowed brows, stared at the blackboard in front of them, with pens and paper in front of them.
A diagram of water ripples was drawn on the blackboard, with the following words written in chalk:
"Strictly speaking, water waves are not simple transverse or longitudinal waves, because the movement of water on the surface is neither perpendicular to nor parallel to the wave velocity direction, but rather a superposition of both."
"When the water is deep enough, every point on the surface will move in a circular motion in place. Let the amplitude be A, the wavelength be λ, and the period be T."
"Assuming A << λ, and the reference frame moving with the waveform shows a steady flow velocity, what are the flow velocities at the highest and lowest points of the wave?"
"Ignoring surface tension and frictional losses, let the density of water be ρ and the acceleration due to gravity be g. Considering energy conservation, please prove that the wavelength and period satisfy the relationship: λ = gT^2/2π."
It's obvious that a physics problem is written on the blackboard.
The physics problem was quite verbose, with a lot of long, rambling text descriptions.
The first question is not difficult; the flow velocities uv and u+v at the highest and lowest points have already been written on the blackboard.
The proof for the second question has not yet been written.
On one side of the blackboard, a young woman stood by the window, wearing frameless glasses, one hand resting on the windowsill, gazing out the window.
Shen Qi, who was secretly observing from the back door of the classroom, made a preliminary judgment: the woman was probably the Physics Competition Team teacher, and the dozen or so students, including Lin Xingyu, were the team members. The female teacher had given the team a physics problem to solve; was this what Lin Xingyu called training?
In Shen Qi's mind, subject competitions in physics, chemistry, and biology should include experimental components. If it's just pure problem-solving, what's the difference between it and math competitions? It's just a difference in question types.
Shen Qi continued to observe secretly. The female teacher who led the Physics Competition Team was not very old, possibly between 25 and 35 years old. Female teachers who led physics competitions were rare. Let's see how good she is.
The female teacher turned to face the team members below the stage and snapped her fingers crisply, "Who wants to come up and write out the proof for the second question?"
Lin Xingyu raised his hand.
"Okay, Lin Xingyu, come up and prove it," the female teacher said.
Lin Xingyu went up on stage and wrote out the proof process with chalk.
1/2△mv1^2+△mg2A+p0△V=1/2△mv2^2+p0△V
Simplified version:
λ=gT^2/2π
Prove
After Lin Xingyu finished writing, he looked at the female teacher.
Smack
The female teacher snapped her fingers again, "Smart."
Lin Xingyu was greatly encouraged. "Thank you for your affirmation, Teacher Mu."
Oh, Teacher Mu. Shen Qi learned the surname of the female teacher of the Physics Competition Team. Where did this Teacher Mu come from? I don't remember her. Then he thought about it. In the past six months, I have been competing in math competitions at home and abroad, and I also went to the Peking University Golden Autumn Camp for training. I haven't been to school much recently. It is normal for there to be personnel changes at school.
Lin Xingyu returned to his seat with a cheerful smile, looking at Teacher Mu with admiration. He had the same expression when he looked at Shen Qi earlier.
Teacher Mu looked like a learned person; she wore glasses and had neat short hair. Then she posed another question:
"There is a type of submarine that uses electromagnetic propulsion instead of a propeller. Water flows through the propulsion pipes, and the viscous resistance between the water flow and the pipe walls and between the water itself is not considered."
"There is a rectangular region in the pipe, with a cross-sectional area the same as the water inlet, and dimensions of a×b×c. A stable magnetic field B is generated within this region by a superconducting magnet. Along the b direction, there is an electrode of size a×b on both the top and bottom faces, which is connected to a DC power supply."
"Assume the current exists only within this rectangular region and is uniform; the steady-state current magnitude is I, the seawater density is ρ1, and the seawater resistance is ρ."
"Assume that after the flow stabilizes, the pressure at the submarine's inlet is p1, the pressure at the outlet is p2, the inlet area is S1 = b × c, and the outlet area is s2."
"1. After determining the steady flow, with the submarine as the frame of reference, calculate the flow velocities v1 and v2 at the inlet and outlet."
2. Calculate the power of the DC power supply after steady-state flow.
Teacher Mu's chalk handwriting was vigorous and powerful, and her hand moved at lightning speed. She finally drew a simplified structural diagram of a submarine propulsion system, and the question was finished.
"This question is adapted from a physics exam question from a certain year's college entrance examination in Zhedong Province. You have 10 minutes to think about it and make a draft." After saying this, Teacher Mu walked towards the front door of Physics Laboratory No. 1.
Shen Qi reviewed the question outside the back door. The question wasn't difficult, but it required the comprehensive application of many physics concepts, including electricity, electromagnetism, mechanics, energy and momentum. Solving the question using pure High School Physics knowledge was no problem.
For most people, high school is the most erudite period of their lives. They have good memories, quick reactions, and sharp thinking. It's not uncommon to see all sorts of knowledge Small Joker and problem-solving queens.
There are generally two trends after graduating from high school: becoming increasingly knowledgeable and cutting-edge, or becoming mediocre.
The former is less common, while the latter is more common.
Youth is fleeting and precious.
Why not show off while you're young?
This opportunity won't come again.
Time waits for no one, but we should seize every moment to show off.
The characteristic of physics problems is that the thought process dictates everything, supplemented by necessary calculations. In terms of the amount of calculation, most branches of physics cannot compare with mathematics.
However, relying solely on pure mathematical calculation skills without understanding the many formulas and principles of physics will make it difficult to achieve anything significant in physics. Ou Ye, a Calculation Ji, can only major in mathematics, while Shen Qi can cultivate both.
In a very short time, Shen Qi had already mentally calculated the first part of the submarine problem; the amount of calculation was not large.
Just then, Teacher Mu came out of the physics lab through the front door. As soon as she stepped out, she noticed a boy sneaking around outside the back door, peeking into the lab.
Without revealing her true feelings, Teacher Mu went down the stairwell near the front door, walked to the end of the second floor, and then went up to the third floor again, quietly and slowly circling behind Shen Qi.
Shen Qi, engrossed in solving the second part of the submarine problem, didn't notice that a female teacher was standing behind him.
"Is this interesting?" Teacher Mu said softly from behind Shen Qi.
"Nothing interesting... huh?" Shen Qi suddenly turned around. Holy crap, is Teacher Mu a ghost? Why does she walk so silently?
Teacher Mu scrutinized Shen Qi closely, and after a moment said, "Shen Qi, the IMO perfect score champion, why were you eavesdropping on my physics class?"
"Hello, Teacher Mu, I was just passing by." Shen Qi quickly regained his composure.