NOVPUB"Brother Qing Fan, I don’t understand something." After a physics class, Lin Wanning asked about something she didn’t understand, as usual.
"Go ahead." Xu Qingfan shifted his gaze from the scenery, and even though he had been daydreaming the whole class, explaining simple middle school physics was still easy for him.
"The teacher just said that the ice block floating on the water is because the buoyant force equals the weight of the water, so after it melts, the water level won’t change. But why do they always say on TV that when glaciers melt due to global warming, the sea level rises? Shouldn’t it stay the same?" The girl rested her chin in her hand as she asked the perplexing question.
The others, upon hearing this, found it surprisingly reasonable and all eyes turned to Xu Qingfan, waiting for an answer.
"What’s there to be confused about?" He flicked Lin Wanning’s hair playfully, explaining, "Because glaciers aren’t all floating on the water surface, right? There are also many mountains covered with snow, and as they melt, the runoff causes the sea level to rise."
"Oh~ right!" The girl had a sudden realization.
"If there’s a metal ball wrapped in the ice block, after it melts the water level will actually go down. Do you know why?" Xu Qingfan suddenly remembered a problem he had encountered before and asked the group.
"The gravity exceeds the later buoyancy, obviously." Xia Xiaoxiao answered without much thought.
"Buoyancy decreased." Wu Lingyu chimed in, barely three seconds later.
"Right." Zhang Yiyi, enlightened by the other two, quickly understood the reason for the decline.
"Huh?" Only Xiao Ruawen and Lin Wanning were several beats slow, their minds not yet catching up.
"Why did the buoyancy decrease, eh? When it floats on the surface, isn’t it that the forces balance out, gravity equals buoyancy?" Xiao Ruawen asked.
"It’s the metal ball, the ball sinks to the bottom." Xia Xiaoxiao explained.
"I don’t get it." Lin Wanning’s head shook like a bobblehead, intending to seek answers from Xu Qingfan.
"I’m going to use the restroom, you let Xiaoxiao teach you." He patted the girl’s shoulder, stood up, and left his seat.
"Hehe, sure, I’ll understand it before Brother Qingfan comes back!" Lin Wanning promised confidently.
Xu Qingfan just smiled and didn’t answer.
The drinking fountain in their school building was right next to the restrooms, and Xu Qingfan always felt that the water from there was connected to the toilet flushing water. Maybe it was his subconscious, but it smelled weird, so he didn’t bring his water bottle to fill up while going to the bathroom.
Also, the toilets there were all contentious points, like those in Experimental Primary School, with door-equipped squat toilets and Western-style toilets being out of the question, just a seven or eight-meter-long channel and several squatting pits separated by half-meter high walls.
Thus, anyone who dared to take a big one during class break was bound to be laughed at for a week, and more severely, might even be bullied by classmates.
Even someone as tough as Xu Qingfan would not dare to squat during class time, with students coming and going looking at you. It was too socially deadly for one, and who knows if there was someone doing furtive things inside.
When someone finally vacated a spot in the channel, Xu Qingfan took his position. He pulled out his own "big gun" to line up with a row of five or six others for a coordinated maneuver.
The sound of the faucet irrigating instantly drew the attention of the other trickling flows; he didn’t want to be so conspicuous, but his capacity didn’t allow otherwise.
[Damn, why not compare to a black person!]
Fearing that his fellow classmates might feel inferior, Xu Qingfan quickly put on his pants, washed his hands, and left after resolving the fight.
While walking, he habitually made a chin pinching gesture, only to realize that his longest beard had grown five or six centimeters long at some point.
"I need to buy a razor when I get back," Xu Qingfan muttered to himself.
It must be said, time really flies; he was only one meter fifty-something when he first stepped into this campus, and now he is already one meter seventy-three.
It had been almost four months since Lin Wanning had her first period. Originally looking like a primary school student, the young girl had now grown close to one meter sixty, and her small chest was no longer a flat A-cup.
Xu Qingfan noticed this while hanging out the laundry; after returning from a holiday break and coming back to school, the underwear and tank tops the girl usually wore had been replaced by bras that only older girls would wear.
It’s just that she still acts like a primary school student, always sticking close to Brother Fan at the slightest prompt.
[I really need to talk to this silly girl.] Xu Qingfan thought to himself about when to talk to her again, considering behaviors like crawling into bed had clearly crossed the normal brother-sister boundary and really should not happen again.
He had already told Lin Wanning several times before, but each time the young girl just giggled and brushed it off. On the one hand, Lin Wanning hadn’t yet blossomed at that time; on the other hand, the girl was genuinely adorable.
The charm of a young Lin Wanning was irresistible; hence, nothing ever came of these conversations.
[This time, it absolutely must not be left unresolved again!]
After returning to the classroom and settling back into his seat, Lin Wanning pulled out three tissues and eagerly handed them to him, saying, "Brother Fan, I figured it out! After the iron ball sinks, gravity exceeds buoyancy, which is different from the initial state where gravity equals buoyancy, that’s why the water level dropped!"
"Not bad, not bad. What if the iron ball were hollow and the ice melted, causing it to suspend in water, or float on the surface? What then?" Xu Qingfan challenged her knowledge by posing two more questions.
"Ah~ more questions?" the young girl complained, but she still seriously picked up a pen and began scribbling formulas and force analysis diagrams on scratch paper.
[Talking about those topics in front of everyone might embarrass Wanning, better to wait for a moment when we’re alone.]
After a while, the girl exclaimed excitedly, "Brother Fan, I know it! It’s all the same, right?"
"Because the gravity always equals the buoyancy, achieving equilibrium. If the iron ball just touches the bottom, but doesn’t exert pressure on the ground, it remains the same!" Lin Wanning seemed to have truly grasped the chapter on buoyancy, even posing further questions for herself.
"Wanning is brilliant," Xiao Ruawen realized and gave her a thumbs up.
"Right on, keep it up, I’ll reward you with a little red flower," Xu Qingfan mimicked the action of sticking a sticker, pretending to affix a little red flower on her forehead.
"Hee hee~"
Encouraged, the young girl’s confidence soared; she no longer found the challenging physics problems tedious but instead felt a thrilling sense of challenging herself.
The wind blew the curtains against her face, then passed over her head, the evening sun through the glass bathed her body in a warm glow, and the sunset at the school always seemed particularly beautiful.
The last study period then came to an end in such an atmosphere.
...
