6: Chapter 6 A Study Room for One

The tactile sensation was completely identical to last time.

The air around him was instantly sucked away, followed immediately by a cold wind wrapped in dust slamming fiercely into his face.

Jiang Lin immediately let go, placing the two woven bags on the ground, and quickly unstrapped the duffel bag in front of his chest and the tent bag on his back.

He dared not delay in the slightest or waste any physical strength.

He didn't have time to rest, nor did he even look up at the surrounding environment.

He unzipped the pocket of his military overcoat and pulled out the Geiger counter.

He pressed the switch.

The instrument emitted a faint current buzz, the needle jumped once, and then stabilized.

He stared at the needle for a full ten seconds.

The needle swayed slightly between zero point two and zero point three microsieverts per hour.

Although it was quite a bit higher than the background radiation of Jiang City in the Real World, it was entirely within the safe range, a far cry from the threshold that would trigger acute radiation sickness.

"There is no high-intensity nuclear radiation."

Jiang Lin let out a long breath, and his tensed nerves finally relaxed.

The iodine tablets in his pocket wouldn't be needed for the time being.

He stood up and looked up at the sky.

It wasn't that gray morning sky from when he first came over.

It looked like afternoon light.

The dark red sunlight shone diagonally from the west, stretching his shadow into a thin and long black shape dragged across the hardened rust-colored soil.

He didn't know the exact time.

The position of the sun was roughly at one-third the height of the sky, dark red, embedded in the gray canopy like a charcoal ball on the verge of burning out.

Estimated according to experience on Earth, it was probably around three or four in the afternoon.

There were still a few hours before dark.

Enough time for him to set up the camp.

At this moment, he was at the base of a crumbling wall with broken ruins.

It was the same position as when he returned last time.

That is to say, wherever he returned from, when he was teleported back again, he would be in that exact same place.

"All right, time to get to work."

Jiang Lin muttered to himself and began setting up the camp.

He moved the luggage to the base of a broken wall about two and a half meters high, took off his heavy military overcoat, picked up the engineering shovel, and leveled the ground.

The engineering shovel struck the hardened soil with a clanging sound, and the tip of the shovel could only bite off a tiny piece.

He spent about twenty minutes clearing out a flat piece of land two meters wide and two meters long.

Then he set up the tent.

Having the experience of more than a dozen setup practices, he could be considered skilled at it.

The tent poles crossed through the reserved channels of the inner tent, propping it up to form a dome structure, the outer tent was draped over it, and the four corners were fixed with ground nails.

Three minutes later, a khaki single tent was erected in the corner of the wall.

He laid the aluminum foil moisture-proof mat inside and unfolded the sleeping bag.

He took out two solar camping lights, placed the solar panels outside the tent, pressed the four corners with stones, and adjusted the angle toward the west facing that mass of dark red light source.

Then he organized the supplies one by one, moved them into the tent, and put them back in their places according to their functions.

After finishing these, the sun sank another notch toward the west.

The urge to urinate arose, and he decided to dig a toilet first.

He would be staying here for quite a few days in the future, so he couldn't just go anywhere.

Jiang Lin pulled out the engineering shovel and walked about fifty meters outside the broken wall.

This distance was enough to ensure the hygiene of the camp, yet not so far that every trip to the toilet felt like an expedition.

He found a slightly low-lying spot in the terrain.

The dark red soil had a naturally formed small depression here, probably twenty or thirty centimeters lower than the surroundings, as if it had once been washed by water.

He used the engineering shovel to dig a pit at the bottom of the depression, about three shovels deep and two shovels wide.

The dug-out dark red soil was piled at the edge of the pit, saved to shovel a handful of dirt over it after each use.

A wilderness survival toilet, to put it bluntly, was just a pit with a dirt cover.

Fifty meters from the camp, downwind, in a low-lying area.

That was enough.

Having solved the toileting issue, he rubbed the shovel against the surface of a nearby rock to scrape off the adhering mud and walked back.

He glanced at the time on his phone.

The time-corrected phone displayed that it was four-thirty in the afternoon.

He carried the collapsible bucket to the puddle.

The water level of the puddle hadn't changed much. The evening light shone diagonally on the liquid surface, making the patterns of the oil film clearly visible.

Jiang Lin unfolded the collapsible bucket, immersed it into the puddle, and lifted a full bucket.

He returned to the camp and took out an empty mineral water bottle, coffee filter paper, absorbent cotton, activated carbon, and fine sand scraped from the base of the broken wall.

The filter paper was folded into a cone, layered with cotton, layered with charcoal, layered with cotton again, and topped with a thin layer of fine sand.

The bottle funnel was placed on the mouth of another empty bottle.

He poured a little grayish-black liquid into it.

The liquid passed through layers of filtration, and the dripping speed was very slow.

One drop, two drops, three drops.

The filtered liquid collected at the bottom of the bottle, changing in color from grayish-black to pale yellow, like tea water that had been brewed many times.

After collecting a small half-bottle, he poured some baking soda into it.

Bubbles surged up with a fizzing sound, lasted for more than ten seconds, gradually weakened, and finally stopped.

The liquid changed from pale yellow to an even lighter off-white, its turbidity increased, and grayish-white precipitates began to appear at the bottom of the bottle.

He left the bottle standing aside to let it settle slowly.

That can wait until tomorrow.

After dealing with the water, the daylight had begun to dim.

The provisions in his stomach had been consumed to six parts full.

Jiang Lin returned to the tent and zipped the windproof zipper with a swift swish.

The moment the zipper closed, the howling sound of the wind outside was suddenly blocked out by more than half.

He collapsed heavily onto the thin moisture-proof mat, thought about it, and then spread out his labor-insurance military overcoat underneath him to use as a mattress.

As soon as this overcoat was padded underneath, a stale smell of mothballs pervaded the tent, which actually smelled quite reassuring.

After resting for a while, he turned on the camping light and hung it on the top hook.

The warm white light instantly lit up, illuminating this two-square-meter small world brightly.

Jiang Lin turned his head to look: on the left were neatly stacked mineral water bottles and biscuits packed in an iron bucket, and on the right were draft paper and a ballpoint pen.

Looking at everything before him, Jiang Lin suddenly twitched the corners of his mouth, feeling somewhat amused.

Outside was the Wasteland, having been destroyed for goodness knows how many years, so desolate that hardly any living grass could be seen.

And what about him?

Hiding in a second-hand tent like a tortoise pulling its head in, with his grandfather's handed-down military overcoat spread beneath him, and a mobile phone, draft notebook, and pen placed in front of him, getting ready to start his high school evening self-study session in this perilous doomsday world.

If this scene were to be filmed into a short video and posted online with the title "People in the Wasteland, just teleported, currently preparing for the college entrance examination", it would probably be roasted by netizens' bullet comments until the server crashed on the spot, and the comments calling him a madman could easily pile up to tens of thousands of floors.

Jiang Lin took a deep breath, took out his phone, switched it to super power-saving mode, and adjusted the screen brightness to just enough to clearly see the characters on it.

He opened the PDF of the Physics textbook and flipped to the chapter on electromagnetic induction.

Faraday's law of electromagnetic induction.

lenzs law.

This was one of his weakest knowledge sections in the Real World.

It was missed during that month of online classes in the first semester of the second year of high school, and he had never truly caught up since then.

When the teacher was lecturing, he understood it half-heartedly, and doing problems entirely relied on blindly applying formulas; if he applied the right one, it was correct, and if he applied the wrong one, he wouldn't even know why it was wrong.

Now he was going to crack this hard nut.

He read very slowly.

He read the page on Faraday's experiment back and forth three times.

Coil, magnet, galvanometer.

Magnet inserted into the coil, the needle deflects; magnet stops, the needle returns to zero; magnet withdrawn, the needle deflects in the opposite direction.

Conclusion: Induced current is generated because the magnetic flux passing through the circuit changes.

He put down his phone and wrote out the experimental process in his own words on the draft paper.

It wasn't copying.

It was pretending he was explaining the problem to Sun Ming.

That fellow Sun Ming's Physics was even worse than his; he couldn't even tell the Left-hand rule and Right-hand rule apart, and would always cram and ask him before every exam.

In the past, he couldn't explain it clearly because he didn't truly understand it himself either.

Now he tried to explain Faraday's experiment to someone who didn't understand it at all.

After finishing writing, he read it once and found that one sentence didn't flow smoothly, so he crossed it out and rewrote it.

He read it another six times, and this time it was smooth.

Then came lenzs law.

That tongue-twister-like expression: The direction of the induced current is always such that the magnetic field it produces opposes the change in magnetic flux that caused the induced current.

He broke it down word by word.

The N-pole of the magnet is inserted into the coil, and the magnetic flux increases.

The induced current needs to oppose the increase, so the direction of the generated magnetic field must be opposite to the magnet.

The magnet's N-pole faces downwards, the magnetic field direction is downwards, so the induced magnetic field must be upwards.

Right-hand screw rule: Thumb points upward, and the four fingers curl in a counterclockwise direction.

Therefore, the induced current is counterclockwise.

He drew this process step by step on the draft paper.

He drew the magnet, marked the N-pole and S-pole, and drew the direction of the magnetic field lines.

He drew the coil and marked the direction of the current.

He gestured the screw rule with his right hand, confirming the direction of the four fingers when the thumb pointed upward.

Then he drew the situation of pulling the magnet out of the coil once more.

The two diagrams were placed side by side.

He stared at these two diagrams for quite a while.

Counterclockwise when inserted, clockwise when withdrawn.

The directions are opposite.

Translated into human language, lenzs law means that the direction of the induced current is always going against you.

When you want the magnetic flux to increase, it deliberately won't; when you want it to decrease, it deliberately won't either.

Like a rebellious adolescent.

Jiang Lin wrote the three words "rebellious period" next to the diagram.

The sky grew completely dark.

The night was already deep.

There was only the sound of the wind, only the sound of his own breathing, and only the rustling sound of the pen tip sweeping across the paper surface.

Inside the tent, that warm white camping light cast his shadow onto the canvas, and the shadow swayed gently with the breeze, appearing slightly lonely.