Sooner or later, our hearts will collide together because of the irregular movement of molecules;

I'm still like sin square + cos squared, consistently;

If you are positively charged, then I am negatively charged, attracted to each other.

……

Forgive Ben Liangzai for not doing his best, but sometimes, after Ben Liangzai worked hard, he found out that he didn't know what it was like to be desperate if he didn't work hard.

The Plum Green Ant needs to determine the speed of sound by measuring the time it takes for a sound to travel from one microphone to another microphone with a known spacing. So you have to make a simple oscilloscope with all the electronic devices you can use, and measure the time difference instead of a stopwatch.

The nature of the sound is used to find the spacing between the points where the sound intensity is greatest, which occurs when the sound is interfering with each other.

Once the wavelength of the sound is determined, knowing the wavelength and frequency of the sound, the speed of sound can be determined.

All of the operations of the Plum Green Ant only provide an opportunity for itself to study the basic properties of sound, and all the techniques used here can also be used to measure the speed of light after being significantly improved.

2 speakers, 2 wires about 6 feet long, sound generator or a monophonic WA V audio file that can be played back from a computer or digital music player, 2 microphones connected to an oscilloscope, tape measure, meter ruler.

Okay, everything is ready.

Wogua looked at the dismantled MP3 and couldn't help but turn around, not wanting to witness this cruel side.

Everything that follows can only be arranged by Li Luant himself, and even if Black Glasses and Jing Qiongshuang want to come forward to help, it will be useless, because everything Li Luant has done cannot be understood unless he has his mind.

But see that he first connected the sound generator to the two oscilloscopes with wiring, connecting the anode of the sound generator to the anode of each speaker. Connect the negative end of the sound generator to the negative end of each speaker.

Next, place the 2 speakers side by side and aim them directly at the microphone. Throughout the measurement, there must be a clear flow between each speaker and microphone.

Then he methodically turned on the sound generator and made sure that the two speakers were working and that the volume was basically the same.

Then connect the microphone to the scope.

After completing this series of operations, the received sound waveform is displayed on the oscilloscope.

Li Luant twisted the interface slightly, and sure enough, the surrounding sounds began to appear in the channel, and if needed, it was possible to adjust the amplitude, timeline, and trigger settings.

Fang Cai's series of operations have proved the feasibility of this action.

Yes！

A flash of joy flashed in Li Luant's heart, and he slowly moved one of the speakers along the line between the speaker and the microphone. At this time, the amplitude of the monitoring display on the oscilloscope has come out.

"Is that okay?"

Although the black glasses are very sure of Li Luant, when looking forward to the result, there is still some nervousness in his words.

Li Luant nodded confidently, "It's totally possible." ”

The current Celsius temperature, because it is in the bottomless underground, and there is groundwater nearby, so at about 20 degrees Celsius, the sound speed at 20 °C is about 343mv/s, the relationship between the sound speed ms and the temperature °C: v=331+0.6T, when using the 440Hz sound that you have just detected, in order to get a speed of 343m/s, the microphone spacing should be 0.78cm.

A 1000Hz sound requires a pitch of 0.343m to get the speed of sound value.

Two beams moving in the same direction are superimposed to form a new waveform. If the crests of these two waves rise at the same time and place, the two waves are considered to be in phase and reinforce each other to form a larger sound. This is called constructive interference. Constructive interference occurs when two sound sources are exactly one of each other by an integer multiple of a wavelength.

And when a wave is a crest at a certain position and a second wave is a trough at the same time, destructive interference occurs.

Li Luant looked at the waveform graph presented by the oscilloscope, and it was obvious that the X-axis to Y-axis curve was a straight line with a negative slope. There is already some clarity in my heart.

It's no wonder that these things don't rule the universe yet, and the only place in this world that can be found in the desert is to find a place in this world that is equal to the frequency of its wings and does not cause serious disruption to its biological clock.

Jing Qiongshuang, black glasses, and Wogua saw Li Luant fiddling for a long time, and finally pointed to the wavelength on the monitor to explain, and finally understood the reason.

It turns out that those things are not that they don't want to come, but they can't come for the time being, and there are very few places in the world that can adapt to and meet the frequency of their wings, and once they find it, they must not leave, otherwise there is a possibility of genocide.

Their own side is an alien intruder on them, and the groundwater in front of them is also a part of their living environment, which has been integrated, although it is slightly inconsistent and takes time to adjust, but this place is completely different from the unfamiliar environment outside, they can adapt to it, find the most suitable point, and then fly over in one fell swoop.

This is also the reason why the black glasses at first said that they obviously looked like they were patrolling and would never dare to cross the river, but later they were not afraid of life and death, and rushed over.

They didn't rush over, they were ready to attack for a long time, and finally found a point that would not hurt their biological clock, and this point, according to Li Luant's observation: the flow of water in this underground river is also regular, as long as there is a regularity, you can find it.

These things are pretty smart.

"No, Husk, you said that the reason why they can't cross the river at all is because of the sound, so I just have to disturb its sound and howl at it? Why do you want to dismantle the MP3 of the pretty boy? ”

Well, I'm still thinking about it.

"The frequency of sound waves that can be heard by the human ear is 20~20000Hz, and when the vibration frequency of the sound wave is greater than 20000Hz, the human ear cannot hear it. Ultrasound gets its name from the fact that its lower limit of frequency is approximately equal to the upper limit of a person's hearing. Therefore, ultrasound waves above 20,000 Hz and sound waves below 20 Hz cannot be detected by the human ear. ”

"The sound waves produced by different parts of the insect body surface rubbing against each other are called frictional vocalizations in the terminology of the insect world, and the method is very common, but the specific articulator construction is varied. A small winged crustacean articulator consists of a tone file and a friction piece. When flapping the wings, the left wing is stacked on the right wing, and the sound file and friction plate rub against each other to produce a sound. The locust's articulators are called file and scraper, respectively, and when the two rub together, they also cause the forewings to vibrate and make a clattering sound. ”

"The sound of the insects flapping their wings when they fly, the vibrations of the bone fragments in the thorax, and the flapping of the left and right wings against each other. Different kinds of insects fly when the frequency of the wing vibration is different, some insects reach 2000 times per second, and butterflies are generally 7.5~13 times, the sound frequency range of our human ears is 16~20000 times per second, so we can hear the wing flapping of mosquitoes, but can not hear the sound of butterflies dancing. ”

"Those things fall into this category, their wings vibrate 10 times per second, that's 10 hertz, which is below the minimum sensory threshold for the human ear, and even if you hear it, you say that you howl and destroy these sound waves and vibrations that are not in the same dimension as you."

Seeing that the face of the wogua had a melancholy look, he raised the modified oscilloscope in his hand.

"Still, it can."

"Is there a way to get rid of them?"

Li Luant nodded firmly, "It can be done, but-" His eyes rolled slightly, and he fell on Wogua, who suddenly hugged his delicate body tightly.

"What? This pretty boy sells himself and doesn't sell his art. ”

If you're not happy, you'll talk nonsense, and if you're not happy, don't want to be happy.

It's strange that the elementary school student called Uncle Ben Liangzai was angry and half dead, and he was called dad by a girl in his early 20s, so excited.

Seeing that the three of them all looked at him, Wogua panicked: it is estimated that the malicious light flashing in the eyes of these three guys is not trying to call him father.

"Wogua-" Li Luant stepped forward and patted him on the shoulder, "Didn't you always want to establish your heart for heaven and earth, establish your life for the people, continue your education for the saints, and open peace for all generations?" Now the opportunity for you to become a glorious Young Pioneer has finally come in your anticipation! ”

cried, "This pretty boy doesn't want to be glorious, he just wants to be a pretty boy." ”

"Here's your chance to be a pretty boy!"

"I don't want to be a pretty boy now, whoever you love should be whom, anyway, this pretty boy is not appropriate."

Yes, it's still flickering.

"Wogua, let me tell you the truth, we still lack a bait now."

"You bad old man is very bad, Ben Liangzi knows that your ass is pouting, it must be no good thing, sure enough, there are good things you never think of Ben Liangzai."

An aircraft worth 100 million destroyed a tent worth one dollar, some people may think that it is not worth it, in fact, there may be 20,000 Indian soldiers inside, or there may be a fully equipped Indian motorized infantry division hidden, and it is also a mechanized unit, and a division of people comes out of a tent.

Time has changed, there is only one person in Wogua, and it cannot constitute the armed force of a division, but it hides more than a billion yuan of love for more than a dozen aunts and wives who are ready to contribute, and now they have to sacrifice their lives for the country together?

I heard that I fell in love with a lawyer, and in the end I didn't even have big pants left, is it true?

No, according to Article 18 of the Marriage Act, your pants are your personal belongings and are not the joint property of the husband and wife.

Looking at Jing Qiongshuang and the black glasses, "If you don't go, you will die", Wogua wanted to cry and looked at Li Luant without tears, "shell lang, can I keep my life and contribute to the four modernizations of the motherland?" ”

"I don't think so."

"Can I protest then?"

"It is estimated that the protest will not be effective."

"Can I appeal on the road?"

"It is expected to be refuted by the federal court."

"Then I think-"

"No, you don't want to!"

Gold Ingot: "......"

I haven't said anything yet, I just came down from Mt. Akina, and you even welded the car door to death for me??

Love puppies?

I like it.

I have a dog in my thirties here, do you want it?

What about being alive in your thirties?

You're so humorous, I love it.

"Hehe-" Wogua sneered twice, looking at Li Green Ant with grief and indignation.

How sad can you be? It's like sticking a dog's head in the snow.

If you are not afraid of ghosts and people, you are afraid of dogs and dogs.

Grow a face and do all the dog things. Are you a dog or am I a dog? Being a dog really has to learn from you. You don't do anything that gets close to people. Compared to you in terms of being a dog, I'm really not as good as you, let's be a dog in the next life, otherwise it's a pity.

Sure enough, the biggest natural enemy of this pretty boy is still a dog.

But it's okay, there is no shortage of dogs in the hit, so go quickly.

Let's both take a step back, I'm not going to be a dog anymore, and you don't want to be a human either.

Looking at the nest melons that appeared in front of those insects like a piece of pork belly, the insects by the river saw that the target was lost and recovered, and they were really excited.

Using a similar principle, the speed of light can also be measured by this time, using an intentional device that determines the wavelength of a known frequency of light by measuring the spacing between destructive interference points. The measurement method is more stringent because the speed of light is much faster than the speed of sound, but the basic method of measurement is the same and can be used to measure any kind of sound or wavelength of light.

Here, just get the speed of sound of these things and determine the frequency is enough.

The speed of sound can be determined if the wavelength and frequency of the sound wave are known, and the wavelength of a sound wave of a given frequency can be determined by finding the spacing between the points where it produces destructive interference.

Wogua showed two bare arms, trembling and trembling with the beating, and looked at the three people in the cave with grief and indignation, "Am I like this, does it seem very tempting?" ”

Jing Qiongshuang held back a smile, "It's very tempting, there will be no more tempting stunner in the world than you." ”

In order not to be this bait, you can even say such shameless words.

Phew, you are cheap, you are a greedy and beautiful boy!

"Buzz—"

The movement on the shore began to stir because of the food that suddenly broke into view.

If you hadn't suddenly intruded into my life, how could I have let go of the loneliness of stubbornness.

If you don't say anything about loving me, you can do everything you want to love my dog, and then it's up to me to see my teeth.

The groundwater is gurgling and rattling—

Wo Gua "Gu Dong" swallowed his saliva, not very sure, "shell Lang, you really promise to be able to keep a beautiful boy in your mouth before they break over, this beautiful boy feels that his little waist can't help them for a minute, what can you take to marry a daughter-in-law without a male dog waist?" ”

？？

"Shell Lang? Dung beetle? ”

Still no one answered.

Wogua panicked: Could it be that in order to contribute to the organization, he didn't run to a well-off life together when he came, and he successfully met in Jinggangshan, and he had to give away his life, and the organization had to abandon himself because of his handsomeness?

"Dong Yu Dong Yu, call Zero Nine? Zero Nine received please answer. ”

"A mountain carving? Rattlesnake? Dung beetle? Groove ————!! ”

Wogua's call has not yet reached people's hearts, but his has already stirred up a chain reaction of the butterfly effect, causing the biological clock that would have taken a while to be adjusted to be accelerated by the restless hearts of those bugs.

There's a double fucking summon here.,Ready to attack directly past the monster.。

What a.

Wogua shook his ass, saying that he didn't want to be this bait anymore.

Whoever loves to be should go, anyway, this pretty boy is not appropriate.

But there was no one who shouted for a long time just now, and as soon as the butt poked down the hole, he was kicked out, and the nest melon squatted on the ground with a buttocks, knocking to the tailbone, and the pain in his heart had not had time to shout out for a long time, and a group of wasps had already swaggered across the river.

"Hum—"

"Buzz—"

！！

"it!!"

"Shell Lang, they're coming, they're coming!"

How does it feel like a swarm of bugs flapping their wings towards you, ready to gnaw you clean? It's hard to say that Wogua hasn't experienced it before, but now it's experienced: this is really fucking magnificent, steaming clouds, and broken liver and intestines!

He would rather have hundreds of big girls rushing towards him than leave his chest exposed to the insect claws of imperialism to be trampled on.

"shell lang, don't you have a plan A, take it out quickly, this pretty boy is about to sacrifice his life for the country!"

Twenty meters –

Fifteen meters –

Ten meters –

Five meters –

These things move fast, and they blink in front of Wogua in just an instant.

It is said that before people die, the experience of a lifetime will emerge like a marquee, and in the end only the most important scene and the biggest regret will be left, and Wogua thought a lot when that moment came, but in the end there was only one sentence.

His mother drank so much water just now, and she was still holding her pee and didn't finish urinating, did it get on her ankle when she messed up just now? How do you get wet?

Before this biggest regret could be issued, there was a faint strange breath in the air, and Wogua couldn't say what it was, but when that unusual thing appeared, he saw that the originally menacing insects suddenly fell to the ground as if they were hit by a meteor, and they all fell to the ground, motionless.

？？？？

！！

Before he could make a big face, the black glasses came out of the hole with solid fuel, and set the insects on fire, burning them clean, and a foul stench filled the air with a "crackling" sound, piercing the wings of his nose.

Wogua was stunned and looked at the three people who came out of the cave, and the three of them looked at Wogua shaking like sieving chaff and their faces like earth, and they only felt funny.

Li Luant stepped forward and grabbed him, and put on his clothes angrily, "Next time, Ben Liangzi will believe you, Ben Liangzi is a stupid dog!" ”

The figure that walked away was not a figure, it was loneliness, and a wounded soul with nowhere to be placed.

I originally thought that the growth of the Great Wall was in my heart, and your growth was in my body, but the years have made me know that I don't have to wait for anyone except express delivery.

Originally, my brother bought me lipstick, and I put my brother's mouth red, and I want to be with you in the morning and twilight, mmmm

Originally, I thought that our couple's screen name, I used the whale to fall north and south, and you called the shark to drop things, but now this beautiful boy has been determined, and the answer range between me and you is between plus 7 billion and minus 7 billion.

People are gone, smoke knows, I'm gone, who knows.

Looking at the lonely back of Wogua, Li Luant slightly, "Did we go too far just now?" ”

Jing Qiongshuang was solemn, "That's right, I think so too." ”

"So next time you let him be bait, don't kick his ass again."

In the dark, the dark glasses replied faintly.