Resonance refers to a physical system vibrating at a certain frequency with a larger amplitude than other frequencies.
At the resonance frequency, a small period of vibration could produce a large vibration because the system stored a large amount of kinetic energy.
There were many instruments and devices that needed to be manufactured using the resonance principle, such as the familiar earthquake instrument, fluorescent lamp, electronic watch, various musical instruments, and so on.
However, it was also extremely harmful, such as mechanical damage, ground resonance, infrasonic resonance, and the imminent collapse of the bridge.
In history, there were many examples of bridges collapsing due to resonance.
For example, in the early 19th century, a team of Napoleon soldiers walked through a bridge in Angers, France, with a majestic and uniform pace under the command of their commander. When they reached the middle of the bridge, the frequency of the march was exactly the same as the natural frequency of the bridge, which increased the vibration of the bridge.
When its amplitude reached its maximum and exceeded the pressure resistance of the bridge, the bridge trembled violently and eventually collapsed, causing many soldiers and civilians to fall into the water and die.
In November 1940, the Tacoma Strait suspension bridge, which was the third largest suspension bridge in the world at that time, had only been officially opened for four months. Because of the wind, the bridge produced uncontrollable vibrations and distortions driven by the resonant frequency. Finally, the middle part of the bridge collapsed and the bridge was destroyed, becoming the most representative failure case of modern bridges.
There were even more ridiculous things. In Korea, there was once a 39-story building. Just because there were more than a dozen people practicing fitness exercises in the gym on the 12th floor, the frequency of the beating happened to be the same as the natural frequency of the building, causing the building to shake for ten minutes. If it hadn't stopped in time, the building wouldn't have escaped the fate of collapsing.
The wooden bridge in front of Tang Xiu was only slightly trembling now. The frequency should be close to that of the previous one, but not completely consistent yet. Otherwise, it would have instantly shattered and broken.
Although there was only a knee-high stream below, it was not worth it if someone was frightened or injured.
The black-faced instructor was maintaining order by the wooden bridge. Upon seeing Tang Xiu coming over, he waved his hand and said,"Don't be anxious. Everyone has to line up in an orderly manner!”
Obviously, they thought that Tang Xiu was eager to cross the bridge and continue forward.
"Instructor, you guys are on the verge of courting death!”Tang Xiu's words were shocking.
This time, not only did the black-faced instructor slow down, but even the students from the other faculties slowed down. They wanted to see who dared to speak to the instructor like this.
The black-faced instructor frowned and asked in confusion,""What do you mean?"
"Right now, the frequency of everyone's footsteps across the bridge is already close to the natural frequency of the bridge itself. Who knows, if any class happens to bump into the right class, that will be the outcome of the bridge collapsing!”
Tang Xiu slightly explained the principle behind it, but the instructor was still confused and his dark face was full of disbelief.
However, the students nearby immediately reacted. They could not forget this kind of knowledge that they had only learned in high school so quickly.
"No way. I'm on the bridge. Why don't I feel anything?”
"By the time you feel it, it will be too late!”
"What he said makes sense. Every bridge has a natural frequency. This kind of wooden bridge has been in disrepair for a long time and its structure is damaged.”
"Then aren't we on the verge of death?”
Especially the freshmen from the Physics Department. They gathered in front of the bridge and muttered,
"The formula for calculating the natural frequency is A=(k/m)×2, so I need to know the stiffness coefficient k and the mass m of the bridge.”
"If only we had a vibration sensor, we could have measured it. Even if we had a strain gauge, it would be fine!”
"There's no need to go through so much trouble. We can use a heavy hammer to hit some parts of the bridge, causing the bridge to vibrate to measure its natural frequency.“
Upon hearing the students 'conversation, the black-faced instructor also realized the importance of the situation. If the students were to suffer casualties due to his negligence during the field training, the pressure on the fishing boat would be huge. He hurriedly asked Tang Xiu,
"What do we do now?"
"Very simple!" "Tell the students not to march across the bridge together, but to walk over at will." Tang Xiu indifferently said,"This way, everyone's footstep frequency is different, and they will interfere with each other. Even if the frequency matches, it won't be able to set off any waves!"”
The black-faced instructor nodded and quickly ran to the bridgehead to tell the other instructors about this matter. It immediately attracted a lot of attention.
Next, all the students who crossed the bridge strolled over as if they were taking a stroll.
In the class, Shen Qian came over curiously.""Tang Xiu, you're really something. How did you find out that the bridge was shaking?”
Tang Xiu pointed at his eyes and pretended to be mysterious,"Did you notice anything different about my eyes?”
Hua Zhengjun came over and stared at it for a moment. He hesitated and said,""Could it be that it's darker?"
Wang Si Yan sized it up for a moment and said thoughtfully,"Tang Xiu, you didn't open your Shura Eye, did you?”
Shen Qian patted his head and said,"Naruto, watch less."”
"Hey!" "Haven't you noticed that my eyes are full of wisdom and have the spirit to see through all illusions?" Tang Xiu sighed and shook his head.”
The three of them were silent for a moment before saying in unison,""Shameless!“
This book comes from：m.funovel.com。