Can you make a phone call in a vacuum? Why?

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The simple answer is: No. In a vacuum, you can't even breathe, so how can you make a phone call? Aliens are another matter.

But if an astronaut is wearing a space suit and a sealed helmet, of course he can make a phone call comfortably, because a space suit is a small spaceship used by one person, with air and supplies inside. There is a communication device inside the space suit, and the microphone is close to the mouth, so the phone call is just talking, and any casual words can be transmitted.

Radio waves do not need air to propagate, and the more vacuum the space, the higher the propagation efficiency. All electromagnetic waves, including visible light, do not need a propagation medium, and propagate fastest in a vacuum, at 300,000 kilometers per second. This is how the sun's electromagnetic radiation travels through 150 million kilometers of highly vacuum space to reach our Earth.

Telephone calls also rely on radio waves, which can be transmitted through wires or wirelessly. If this is the case, why can't we make a phone call in a vacuum?

To explain this problem clearly, we must first understand the principle of making a phone call.

The telephone is a great invention of mankind. It appeared in the 18th century and was officially used as a telephone after the mid-19th century. The first person to apply for a patent for the invention of the telephone was British inventor Alexander Graham Bell. He applied for a patent for the telephone in March 1876, and is therefore known as the father of the telephone.

However, the United States Congress passed Resolution 269 on June 15, 2002, confirming Antonio Meucci as the inventor of the telephone because Meucci first demonstrated his invention to the public in 1860 and announced it in an Italian newspaper.

So there are two fathers of the telephone in the world. Who is the real father of the telephone? There is no conclusion in the world, so we will not try to distinguish it. Today we will just briefly understand the principle of the telephone.

After the invention of the telephone, it has gradually developed from the simplest point-to-point short-distance calls to long-distance multi-person calls, video calls, etc., from manual switches to dial-up phones, program-controlled phones, dual-tone multi-frequency phones, etc., and new modern technologies are emerging in an endless stream, such as Internet phones, digital mobile phones, video calls, etc., with more and more varieties and conveniences.

But no matter what kind of tricks, the essence of the telephone has not changed, that is, one person speaks and the other person answers, communicating with each other through voice. The basic principle is: people emit sound waves through their mouths, transmit the sound waves to the microphone, and the sound waves are converted into audio vibrations through the microphone pickup, and then the vibration strength is converted into changing electric current.

The electric current is transmitted to the recipient's phone through wires or radio waves. The receiver in the phone converts the electric current into audio vibrations through a process opposite to that of the transmitter, and then converts it into voice sound waves, which are transmitted to the human ear through the air. In this way, a communication channel is formed between the two parties on the phone call.

Through the understanding of the above basic principles of telephone, we should be clear that in addition to using radio waves to transmit, telephone also needs a fundamental and indispensable transmission tool - sound waves. Without sound waves, there will be no transmission and reception of telephone.

Sound waves cannot form in a vacuum, so you can't make phone calls.

Sound waves are mechanical waves. The difference between mechanical waves and electromagnetic waves is that electromagnetic waves do not need a medium to propagate, while sound waves must have a medium to propagate. The simplest and most common medium is air. Sound waves can only propagate by vibrating the air and other media. The speed of sound waves in air is about 340 meters per second, and the speed of sound waves in steel is even faster, about 5200 meters per second.

There is no propagation medium in a vacuum. Even if a person is not suffocated, his or her voice cannot be transmitted to the microphone. If the person answering the phone is also in a vacuum, the sound cannot be transmitted to the eardrum through the external auditory canal because there is no sound wave vibration, and the person cannot hear the sound from the microphone.

There is now a bone conduction speaker and receiver that converts electrical signals directly into sound waves, and then converts the sound waves into mechanical vibrations of different frequencies, which are transmitted to the human brain through the human skull, bony labyrinth, inner ear lymph, spiral organ, and auditory center without being transmitted through the air.

But there is also a prerequisite, that is, there must be air in the human lungs, mouth, and throat to emit sound waves; and even if the receiver can directly convert it into sound through bone conduction, even if he holds his breath in a vacuum, the low air pressure will draw liquid and gas out of the body, and he will swell and die before he suffocates to death.

The human voice and sound receiving system both require air.

The ability of a person to make sounds is achieved through the participation of multiple systems and organs. First of all, the respiratory system is the power system for pronunciation. The airflow generated by the lungs exerts pressure on the glottis, causing the vocal cords to vibrate, which can produce basic sounds. The basic sounds are modulated by the resonance cavities such as the nasal cavity, pharyngeal cavity, oral cavity, and chest cavity, and then through the activities of the articulatory organs such as the lips, tongue, teeth, and palate, before they can finally form the sounds that people hear.

The pronunciation of a person is a bit like a wind instrument. The vocal cords are equivalent to the reeds, and the genitals are equivalent to the resonance cavities such as the pharynx, nose, and mouth. The power source is the airflow. If there is a problem in any of these aspects, it will affect the pitch, timbre and intensity of the sound. Many people with pharynx, mouth, and nose problems have abnormal pronunciation.

The basic requirement for these organ structures or wind instruments to function is that they must have the participation of air. Without airflow, the source of sound is cut off, and any resonance and articulation are useless. No sound can be produced, and there will be no sound waves.

Human hearing is also the result of sound waves being transmitted to the eardrum, through a series of delicate mechanisms such as the hammer bone, and then reaching the cochlea. The cochlea converts the vibration signals into electrical signals, which are transmitted to the brain through nerve fibers connected to the cochlea. Only after the brain's empirical processing can people feel various sounds.

Without air, there is no sound wave transmission. Therefore, even if the headset is worn on the ear, it cannot be transmitted from the external auditory canal to the eardrum, and the phone cannot be answered. In fact, the invention of the telephone is to simulate the process of people making and receiving sounds. No matter whether anyone makes or receives sounds, the most important bridge is air.

Therefore, in a vacuum, people cannot survive, and they cannot make any sound, and therefore cannot make or receive calls. Welcome to discuss, thank you for reading.

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