Sooner or later, our hearts will collide together due to the irregular movement of molecules;
I am still like sin squared + cos squared, always the same;
If you are a positive charge, then I am a negative charge, attracting each other.
…
Forgive me for not trying my best, but sometimes, after I work hard, I realize that if I don’t work hard, I don’t know what despair feels like.
Li Lvyan needs to determine the speed of sound by measuring the time it takes for sound to travel from one microphone to another microphone with a known distance. Therefore, he needs to use all available electronic equipment to build a simple oscilloscope and then measure it. Time difference instead of stopwatch.
Use the properties of sound to find the distance between the points of maximum sound intensity, which occurs when sounds constructively interfere.
Once the wavelength of sound is determined and the wavelength and frequency of sound are known, the speed of sound can be determined.
All of Li Green Ant's operations only provided him with an opportunity to study the basic properties of sound. All the techniques used here can also be used to measure the speed of light after significant improvements.
2 speakers, 2 cords approximately 6 feet long, sound generator or a single tone WA V audio file that can be played through a computer or digital music player, 2 microphones connected to an oscilloscope, tape measure, meter stick.
OK, everything is ready.
Wo Gua looked at the torn apart MP3 player and couldn't help but turn around, not wanting to witness this cruel side with his own eyes.
Everything that follows can only be arranged by Li Luyi himself. Even if Black Glasses and Jing Qiongshuang want to come forward to help, it will be of no avail, because everything Li Luyi has done cannot be understood unless he has his mind.
But I saw that he first connected the sound generator to the two oscilloscopes with wiring, and connected the anode end of the sound generator to the anode end of each speaker. Connect the cathode end of the sound generator to the cathode end of each speaker.
Secondly, place the two speakers side by side and aim them directly at the microphone. During the entire measurement process, there must be an unobstructed space between each speaker and the microphone.
Then he methodically turned on the sound generator and ensured that the two speakers were working and had basically the same volume.
Then connect the microphone to the oscilloscope.
After completing this series of operations, the received sound waveform will be displayed on the oscilloscope.
Li Luyi slightly twisted the interface, and sure enough, the surrounding sounds began to appear in the channel. If necessary, it is possible to adjust the amplitude, timeline and trigger settings.
The series of operations just now have proven the feasibility of this action.
Yes!
A flash of joy flashed in Li Lvyan's heart, and he slowly moved one of the speakers along the line between the speaker and the microphone. At this time, the amplitude displayed on the oscilloscope was already displayed.
"May I?"
Although Black Glasses was very confident about Li Lvyan, there was still a hint of nervousness in his words as he looked forward to the result.
Li Lvyan nodded confidently, "Absolutely."
The current temperature in degrees Celsius is around 20 degrees Celsius because we are in a bottomless underground and there is groundwater nearby. The speed of sound at 20 degrees Celsius is about 343mv/s. The relationship between the speed of sound ms and the temperature in degrees Celsius: v=331+0.6 T, when using the 440Hz sound that I just detected, in order to obtain the sound speed of 343m/s, the distance between the microphones should be 0.78cm.
A 1000Hz sound requires a distance of 0.343m to obtain a wait-and-see sound speed value.
Two waves moving in the same direction are superimposed to form a new waveform. If the peaks of the two waves rise at the same time and in the same place, the two waves are considered to be in phase and strengthen each other to form a larger waveform.
sound. This is called constructive interference. When two sound sources are separated by exactly an integer multiple of the wavelength, constructive interference will occur.
When one wave is a peak at a certain position and a second wave passes through this position at the same time, it is a trough, destructive interference will occur.
When Li Lvyan looked at the waveform displayed on the oscilloscope, it was obvious that the curve between the X-axis and the Y-axis was a straight line with a negative slope. His mind became somewhat clear.
No wonder these gadgets don’t rule the entire universe until now. It turns out that you have to find a place in this world where the flapping frequency of its wings can be equal to it without causing serious interference to its biological clock. This can only be achieved in the desert.
Jing Qiongshuang, wearing black glasses, and Wogua saw Li Lvyan fiddling with it for a long time, and finally pointed at the wavelength on the display to explain, and finally understood the reason.
It turns out that it’s not that those things don’t want to come, but they are temporarily unable to come. There are very few places in the world that can adapt to the frequency of their flapping wings. Once you find one, you must not leave, otherwise there is the possibility of genocide.
For them, they are foreign intruders, and the groundwater in front of them is also part of their living environment and has been integrated into one. Although it is slightly inconsistent and requires time to adjust, it is completely different from the unfamiliar environment outside.
You can adapt yourself, find the most suitable point, and then fly there in one fell swoop.
This is also the reason why Black Glasses said at first that they seemed to be wandering around and would never dare to cross the river, but later they showed no fear of life or death and rushed over as soon as possible.
They didn't rush over, they had been preparing for a long time, and finally found a point that would not harm their biological clock. And at this point, according to Li Green Ant's observation just now: the flow of water in this underground river is also regular, as long as
If there is a pattern, you can find it.
These things are pretty smart.
"No, dung beetle, you said that the reason why they can't cross the river is because of the sound. Then I just need to disturb its sound and howl at it."
Okay? Why do you want to tear down this handsome guy’s MP3?”
Yes, I'm still thinking about it.
"The frequency of sound waves that the human ear can hear is 20 to 20,000 Hz. When the vibration frequency of the sound wave is greater than 20,000 Hz, the human ear cannot hear it. Ultrasonic waves are named because their lower frequency limit is approximately equal to the upper limit of human hearing. Therefore, ultrasonic waves are higher than 20,000 Hz.
Ultrasonic sound waves and sound waves below 20 Hz are not detectable by the human ear."
"When different parts of the insect's body surface rub against each other, the sound waves produced are called frictional vocalization in the terminology of the insect world. The method is very common, but the specific structure of the vocal organ is diverse. The vocal organ of small crustacean insects with wings
It consists of a sound file and a friction piece. When flapping its wings, the left wing overlaps the right wing, and the sound file and the friction piece rub against each other to produce sound. The locust's sound organs are called sound files and scrapers respectively. When they rub, they also produce sound.
It causes the vibration of the forewings to make a clicking sound."
"When insects fly, the flapping of their wings, the vibration of the thorax bones, and the sound caused by the flapping of the left and right wings against each other. Different types of insects have different wing vibration frequencies when they fly. Some insects can beat up to 2,000 times per second, while butterflies
The vibration frequency of the sound we hear by human ears ranges from 16 to 20,000 times per second, so we can hear the flapping of mosquito wings but not the sound of butterflies dancing.
"
"Those things fall into this category. Their wings vibrate 10 times per second, which is 10 Hertz, which is lower than the lowest hearing threshold of the human ear. Even if you hear it, you can howl and destroy these sound waves and vibration amplitudes that are not relevant to you.
Even a creature with a situational dimension cannot do it."
Seeing a disappointed look on Wo Gua's face, he raised the modified oscilloscope in his hand.
"But, it can."
"Is there a way to eliminate them?"
Li Green Ant nodded firmly, "It can be done, but -" his eyes turned slightly and fell on Wo Gua, who immediately hugged his delicate body tightly.
"What are you doing? This handsome boy is not a prostitute but a prostitute."
If this handsome boy is not happy, he will talk nonsense. If this handsome boy is not happy, you should not be happy either.
It’s strange that a primary school student is so angry when he calls me uncle, but he is so excited when a girl in her early 20s calls her dad.
Seeing the three people all focusing on him, Wo Gua panicked: I guess the ill-intentioned glint in the eyes of these three guys was not because they wanted to call him daddy.
"Wo Gua——" Li Lvyan stepped forward and patted his shoulder, "Didn't you always want to establish a heart for the world, establish a destiny for the people, carry on the unique knowledge for the saints, and create peace for all generations? Now let you
The opportunity you have been waiting for to become a glorious Young Pioneer has finally arrived!"
She cried, "I don't want to be a handsome boy, I just want to be a handsome boy."
"Here's your chance to become a handsome boy!"
"I don't want to be a handsome boy now. I'll be whoever you love. Anyway, I'm not a handsome boy."
Okay, I can’t fool you anymore.
"Wogua, to tell you the truth, we still lack a bait."
"You are such a bad old man. This handsome boy knows that when you stick your butt out, something bad will happen. Sure enough, if there is a good thing, you never think of this handsome boy."
A plane worth 100 million destroyed a tent worth 1 dollar. Some people may think it is not worth it. In fact, there may be 20,000 Indian soldiers inside, or there may be a full Indian motorcycle infantry division hidden inside, and it is also a mechanized force.
, a division of people came out of a tent.
Time has changed. There is only one person in Wo Gua, who cannot constitute an armed force of a division. He only has a love of more than one billion that he has prepared to contribute to more than ten aunts and wives. Are they going to die for the country together now?
?
I heard that if you fall in love with a lawyer, you won't even have your underpants left in the end. Is this true?
No, according to Article 18 of the Marriage Law, your underwear is your personal belongings and is not the joint property of husband and wife.
Looking at the eyes of Jing Qiongshuang and the black glasses that said "If you don't go, you will die", Wo Gua looked at Li Lvyan with tears in his eyes, "Shit Beetle, I can save my life to contribute to the four modernizations of the motherland."
?”
"Probably not."
"Then can I protest?"
"The protest is probably ineffective."
“Then can I appeal on circuit?”
"It will probably be rejected by the federal court."
"Then I think-"
"No, you don't want to!"
Jin Yuanbao: "..."
I haven’t said anything yet. I just came down from Qiu Mingshan and you actually welded the car door shut for me??
Do you like puppies?
I like it.
I have a thirty-year-old dog here, do you want it?
Are you still alive in your thirties?
You are so funny, I like it very much.
"Haha——" Wogua sneered twice and looked at Li Lvyan with grief and anger.
How much sorrow can you have? 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.
You have a good face and do all the dog things. Are you a dog or am I a dog? I really have to learn from you about being a dog. You don’t do anything that has anything to do with people. Compared with you in terms of being a dog,
I'm really not as good as you. I'll just be a dog in my next life, otherwise it would be a pity.
As expected, this handsome boy’s biggest natural enemy is a dog.
But it’s okay, there is no shortage of dogs in your destiny, so if you want to leave, leave quickly.
Let's each take a step back. I won't be a dog anymore, and you won't be a human either.
Seeing the nest of melon appearing like a piece of pork belly dangling in front of the insects, the insects by the river became excited when they saw their target was lost and found again.
Using a similar principle, the speed of light can also be measured by using a commercially available device to determine the wavelength of light of a known frequency by measuring the distance between destructive interference points. The measurement method is more
Strictly because the speed of light
It is much faster than the speed of sound, but the basic method of measurement is the same and can be used to measure the wavelength of any sound or light.
Here, it is enough to get the speed of sound of these things and determine the frequency.
If the wavelength and frequency of a sound wave are known, the speed of sound can be determined. The wavelength of a sound wave of a given frequency can be determined by finding the distance between the points where it produces destructive interference.
Wo Gua exposed his two bare arms and trembled with the beat. He looked at the three people in the cave angrily, "Do I look very attractive like this?"
Jing Qiongshuang suppressed her laughter and said, "You are so alluring. There is no more alluring beauty in the world than you."
In order not to be used as bait, you even said such shameless words.
Bah, you are despicable, you are greedy for this handsome boy’s body!
"Buzz buzz-"
The movement on the shore began to stir because of the food that suddenly broke into sight.
If you hadn't suddenly broken into my life, how could I have let go of the loneliness I clung to.
If you don't say anything about your love for me, you'll do all the stupid things you love about me, and then you'll have to look at my teeth.
The underground water is gurgling and making a sound——
Wogua "Gudong" swallowed his saliva, and said uncertainly, "Shit Beetle, you really guarantee that you can keep the pretty boy in your mouth before they come over. I feel that my small waist can't help their teeth chattering for a minute.
, How can you get a wife if you don’t have a bitch?"
??
"Dung beetle? Dung beetle?"
Still no one answered.
Wo Gua panicked: Could it be that he had made a contribution to the organization and had to risk his life if he did not go to a well-off society together and successfully reunited in Jinggangshan, and the organization would also abandon him because of his handsomeness?
"Dongyao, Dongyao, call Lingjiu? Lingjiu has received it, please answer."
Wo Gua's call has not yet reached people's hearts, but his bullshit has already triggered a chain reaction of the butterfly effect, causing the biological clock that originally took some time to be adjusted to be accelerated by the restless hearts of those bugs.
This damn thing also has a double summon, so be prepared to jump over the monsters and attack directly.
What a fuck.
Wogua shook his butt and said he no longer wanted to be this bait.
Whoever wants to take it should go, anyway, this handsome guy is not the right one.
But after shouting for a long time, no one was there. As soon as his butt reached the hole, he was kicked out. Wogua squatted on the ground on his butt and hit his tailbone. Before he could express the pain in his heart, a swarm of wasps appeared.
I have crossed the river in a big way.
"Buzz——"
"Buzz buzz-"
!!
"Fuck!!"
"Dung beetles, they're coming, they're coming!"
How does it feel when a swarm of bugs flap their wings and rush towards you, ready to eat you clean? I haven’t experienced it before, so I can’t say, but now I have experienced it: it’s really fucking spectacular, the clouds are steaming and the clouds are shining, and my heart is broken!
He would rather have hundreds of big girls rushing towards him than expose his chest to the insect claws of imperialism and let others trample on him.
"Dung Beetle, don't you have a plan A? Come out quickly, this handsome boy is about to die for the country!"
Twenty meters——
Fifteen meters——
Ten meters——
Five meters——
These things moved very fast, and they were in front of Wo Gua in just a blink of an eye.
It is said that before a person dies, his life's experiences will appear like a revolving lantern, leaving only the most important scene and the biggest regret in the end. When that moment came, Wo Gua thought a lot, but in the end he only had one sentence.
Damn, you drank so much water just now, and you were still holding back your pee. Did you pee on your ankle when you urinated? Why is it so wet?
Before this biggest regret could be expressed, there was a faint unusual smell in the air. Wo Gua couldn't tell what it was, but when that unusual thing appeared, the menacing bug suddenly seemed to be caught by a meteor.
They all hit the ground and fell to the ground, motionless.
????
!!
Before Wo Gua had time to look overjoyed, Black Glasses came out of the hole holding a solid fuel, lit the bugs on fire, and burned them all. An unpleasant stench filled the air with a "cracking" sound.
inside, piercing the nose.
Wo Gua gaped at the three people who filed out of the cave. The three of them saw Wo Gua shaking like chaff and his face as pale as earth, and they only found it funny.
Li Lvyan stepped forward and grabbed him, and Wo Gua put on his clothes angrily, "Next time I trust you, this handsome boy is just a stupid dog!"
The figure walking away is not a figure, but loneliness and a wounded heart that has nowhere to rest.
I originally thought that the Great Wall is in my heart and you are in my body, but time has taught me that I don’t have to wait for anyone except express delivery.
Originally, my brother bought me lipstick, and I made my brother's mouth red. I wanted to spend time with you day and night, um um and ah. Now if you don't like this handsome boy, please donate your eyes to people in need.
I originally thought that as our couple's online names, I would use whales to drop north and south, and you would ask sharks to drop things. Now I have determined that the range of answers between you and me is between plus 7 billion and minus 7 billion.
When people leave, Yan knows it; when I leave, who knows.
Looking at Wogua's lonely back, Li Lvyan asked slightly, "Did we go too far just now?"
Jing Qiongshuang solemnly said, "Yes, I think so too."
"So next time you use him as bait, don't kick his ass."