I failed a course, and the system became my study supervisor.

Chapter 46 Simulated Confrontation (Part )
"Regarding the issue we just raised about the water droplet on the ping-pong ball causing an increase in mass, could you explain how you believe this increase is negligible?"

After calming down, Xu Ling stood up and took the lead.

"We have calculated this theoretically and believe the impact of water contact is minimal."

Yu Wenkai responded.

"Have you conducted any experiments to verify this? Will water contact affect the experimental results?"

Xu Ling continued to ask.

"Well... we didn't conduct an actual experimental verification, but we did run a simulation by temporarily adding a fixed increment to the ping-pong ball."

"Fixed increments? Can they be fixed even if they get wet?"

"We're taking multiple different increments, but the process for each individual is fixed."

"This can't be fixed, right? When water touches the ping-pong ball, won't a small amount of water escape again? Won't the mass change again?"

Xu Ling pursued him relentlessly.

Yu Wenkai looked a little flustered, and his tone was a little hurried:

"Water already has a very small mass. How much of an impact would it have if the mass was reduced further?"

"Mr. Zheng Fang, we can tell you very clearly that we conducted a simulation experiment specifically for this problem, but we added a description of the changes in water quality. In the end, we found that the experimental results would be affected. If we use approximate treatment, we should at least add a second-order correction term."

After saying that, Xu Ling controlled the computer and released the experimental results.

For a moment, several students in the same group were stunned at the same time, staring blankly at Xu Ling's experimental results.

However, Xu Ling had not finished asking questions:

"Mr. Zheng Fang, you just mentioned that you made a prediction about the buoyancy of a ball. Have you conducted any experiments to verify this? Does it align with your theory?"

"We've made this issue very clear. During the ball's sinking and the jet's generation, the liquid will experience a turbulent phase. We can't get a precise calculation result, so we can only give a qualitative inference."

Jiang Yuchen stood up and responded to Xu Ling.

"Okay, we understand."

Xu Ling sat down, and then Qin Qin took the microphone.

"We've noticed that the container you chose for your experiment is long and narrow. Have you considered the air velocity inside the container above the water? Based on our experimental observations, the impact of air velocity cannot be ignored."

"We conducted preliminary experiments to address this issue and found that when the container's drop time is less than 0.3 seconds, the effect is negligible. Our experiments are in good agreement with theory."

This question did not gain any advantage, but Qin Qin was not discouraged and continued to ask:
"Then are the masses of the ping-pong balls you used in your experiment all fixed? The masses of different ping-pong balls may not all be standard, and such fluctuations are unpredictable. Have you considered this issue?"

Jiang Yuchen immediately replied:
"We have considered this issue and calculated the relevant uncertainties, which are all within an acceptable range."

"Then Mr. Zhengfang..."

Qin Qin refused to give up and was about to continue asking, but was interrupted by the time-out notification.

"The discussion is over. Now it's our turn to ask questions. Please prepare your answers."

After saying that, Zeng Boyuan handed the microphone to Liu Chunlin.

"Mr. Zheng Fang, could you please elaborate on your process for calculating the velocity increment caused by the wave-flow focusing effect?"

At this time, the microphone of the affirmative team was handed over to another student from the group. He stood up and said very casually:
"Let me first give you an example to explain the wave focusing effect. We found that if we place a container on a table and press a ping-pong ball into the water, when we release it, the ball will float up and rotate. This is the effect of the wave focusing effect and buoyancy.

Next, please look at this page of the slides. We first establish the coordinate system and list the following differential equations. Then, using Fourier and Laplace transforms, we obtain the following results. By performing the inverse transform, we obtain the final solution. This is followed by its first-order and second-order correction terms.

Liu Chunlin was very satisfied with this answer. He nodded and turned his attention to Xu Ling's group.

"Fellow opponents, you've repeatedly emphasized the non-negligible impact of water on the ball. Could you please elaborate?"

Liu Chunlin hit the nail on the head.

Xu Ling did not panic. He believed in the experimental results of his team:

"We first conducted an experiment. We recorded the movement of the ball in the actual experiment and compared it with the simulation experiment in which water was ignored.

The experimental results are shown below. We clearly found that the ball has a different rotation in actual motion.

Next, we modified the motion model that ignored water contact and added the following correction item.

Finally, we repeated the experiment and found that the experimental results were in good agreement with the theory!"

Liu Chunlin was also very satisfied with Xu Ling's answer and nodded repeatedly.

Even many professors sitting in the audience were impressed by Xu Ling's answer.

"The questioning for the critics is over. Please remain seated for the time being. Now, please allow the judges to judge the two students."

Zeng Boyuan said again meticulously.

Only then did Xu Ling realize that there were judges for this competition. He thought they would be Zeng Boyuan and Liu Chunlin.

"Look at the teacher in the first row!"

Qin Qin patted Xu Ling's arm to remind him.

Xu Ling looked over immediately and saw six teachers in the first row, each holding a small notebook, gathered together to discuss something.

Is this the judge?

Xu Ling suddenly became nervous and his heart beat faster involuntarily.

The rest of the group wasn't much better. Although this was just a mock competition, in everyone's minds it was no less than a formal competition.

Time passed by minute by minute. Watching the judges stretching out their hands to gesture from time to time, and picking up pens to make corrections from time to time, Xu Ling became more and more nervous, and his heart seemed to be squeezed in his throat.

Finally, under the eager gaze of the crowd, several judges returned to their seats, and one of them handed a small notebook to Zeng Boyuan on the stage.

Xu Ling knew that it was the "Book of Life and Death" that recorded the results of the competition!
After browsing the contents of the notebook, Zeng Boyuan cleared his throat and said:
“各位评委对正方同学的评分为：8分、8分、9分、9分、7分和8分。平均分为8.2分。

对反方同学的评分为：7分、9分、8分、9分、9分、8分。平均分为8.3分。”

so close!

Only 0.1 point difference!
but--

Won!

Xu Ling's nervousness suddenly disappeared without a trace, and a huge feeling of joy surged up in him.

"We won! Qin Qin, we won!"

Xu Ling was so excited that he couldn't help but grab Qin Qin's arm and shook it continuously.

(End of this chapter)