Daming: The system rejected my request for salted fish

Chapter 904

"I've told you before that the essence of sound is vibration. Vibration of objects generates sound waves, which then propagate through the air."

"You can do a simple experiment when you get home. Connect a string between two bamboo tubes, stretch them straight, and try to make them communicate."

As Wei Wu spoke, he drew a simple line diagram on the telephone receiver on the whiteboard, and then continued:

"This is called a telephone receiver. It has a receiver and a mouthpiece. Let's talk about the mouthpiece first. The function of the mouthpiece is to convert sound signals into electrical signals."

"There are three key elements inside it: the wire, the metal foil, and the carbon particles. When you speak into the microphone."

"The sound causes the metal diaphragm to vibrate, and the vibration of the diaphragm compresses the carbon particles. The movement of the carbon particles causes the overall structure to change."

"When the structure of the carbon particles changes, it causes a change in resistance, and resistance causes a change in current flow."

While speaking, Wei Wu's hands did not stop, and he directly wrote the process of change on the whiteboard.

Sound wave vibration → diaphragm vibrates accordingly → carbon particle structure changes → resistance changes accordingly → causing current changes.

When Wei Wu was writing and speaking on the podium, the craftsmen below were not standing there in a daze, but were all taking notes in an immersed manner.

At the same time, Wei Wu did not stop and continued to explain:

"Next is the earpiece. The earpiece also has three key components: the wire, the electromagnet, and the metal foil."

"The difference is that the foil of a microphone can be made of copper or silver, but the foil of an earpiece is made of iron because of the magnet."

"A microphone converts sound waves into electric current, while a receiver does the opposite: it converts electric current back into sound waves."

Sound wave → electric current → sound wave.

After finishing this brief process, Wei Wu continued to explain:

"Inside the receiver, the wires are connected to an electromagnet, and the magnetism of the electromagnet is determined by the strength of the current passing through it."

"The current in the other person's microphone, which is changed by the resistor, is transmitted to your side through the line, which will affect the strength of the electromagnet in the receiver."

"When the strength of the electromagnet's magnetism changes, it directly acts on the iron diaphragm of the receiver, causing it to vibrate."

"The iron diaphragm vibrates and produces sound, which converts the electric current into sound waves, so you can hear what the other party is saying."

The strength of the current → the strength of the electromagnet's magnetism → the iron diaphragm is affected and vibrates → the vibration makes a sound.

After finishing writing about the process of converting electric current into sound waves, Wei Wu turned and looked at the craftsmen below the stage.

"I know you don't understand yet, but my request is that you try to build it successfully first."

“Know first what it is, then learn why it is so through study and hands-on practice, and learn knowledge through practice.”

"Of course, I will also explain the relevant knowledge in subsequent classes. So next I will..."

After explaining the principles of the telephone, Wei Wu prepared to officially start today's class.

However, before he could finish his words, a voice called out from outside the door.

"Mr. Vice President, the blacksmith team said that the things you requested are ready."

Hearing this, Wei Wu shook his head and smiled helplessly.

"Forget it, let's just do the last experiment today and start teaching tomorrow!"

While craftsmen are enthusiastic about learning new things, they are even more enthusiastic about experimenting.

So when they heard Wei Wu say that he would not teach, they were not disappointed. Instead, they were full of anticipation for the experiment that was about to begin.

Afterwards, under the leadership of Wei Wu, the craftsmen followed him to the experimental site of the Academy of Science and Technology.

When Zhu Yuanzhang allocated land to the Academy of Science and Technology, he allocated all the land around it except the Academy’s headquarters.

After so much development, the Institute of Science and Technology has already made arrangements for the planning of the surrounding land.

After all, the firearms group experiments with gunpowder, and the blacksmith group smelts iron and metallurgy, and these all require special venues to ensure safety and convenience.