How Do You Know the Speed of an Electromagnetic Wave in a Vacuum?

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Often the first thing that comes to mind when we think about the vacuum in outer space. Space is a vacuum because there is no air and no atmosphere. The work of electromagnetic wave speed in managing the activities of a vacuum is an interesting aspect to think about. Do you know the speed of an electromagnetic wave in a vacuum?

In this article, we help you to know what electromagnetic wave speed in a vacuum is. Along with that, how it works physically and mathematically as well as why it travels in a vacuum. Knowing all these facts will increase your interest in a vacuum many times over. So keep following the rest of the article to know the electromagnetic wave speed of a vacuum.

What is the Speed of an Electromagnetic Wave in a Vacuum?

An electromagnetic wave is a special wave that can travel through outer space. However, mechanical waves are the opposite of electromagnetic waves. They both need a medium to transport energy from one place to another. A practical example of the medium of mechanical waves is sound waves. On the other hand, light waves are a good example of electromagnetic.

Now an important question is how is this electromagnetic wave created? It is created by the vibration of an electric charge. The vibration of the electric charge causes the emergence of a wave where there is an electrical and magnetic component. The energy of an electronic wave takes a medium to flow from one place to another. Electromagnetic waves transport their energy through a vacuum with a speed of 3.00 * 10^8 m/ s. Note that the value of a motion is expressed by the symbol C.

A medium is essential for transporting the energy of electromagnetic waves. At the same time, it is necessary to absorb and extract the energy of those waves. This means that when an electromagnetic wave affects the atoms of a substance, the energy of that wave is absorbed. Due to this energy absorption, the electrons in the atom have to withstand vibrations

When the vibration speed is short, the vibrating electrons produce a frequency equal to that of the electromagnetic wave. This creates a new electromagnetic wave. However, it is true that these vibrations occur for a very short time and delay the speed of the medium waves.

How Do You Know the Speed of an Electromagnetic Wave in a Vacuum?

You already know what an electromagnetic wave is. Now it’s time to find out how its speed works in the case of vacuum. For that, we will show some examples of mathematical terms here. This will allow you to understand deeply.

As we said earlier that an electromagnetic wave takes a physical medium to transport and its speed is 3.00 * 10^8 m/s. To determine the speed of electromagnetic waves in a vacuum takes the peak value of the ratio of electric and magnetic fields.

The whole space is considered a space for the convenience of calculation. This is because a vacuum cleaner creates pressure between the cleaning area and the suction tube. But in space, there are different substances such as pressure which is much less than the planets.

Example: The speed of electromagnetic waves depends on the radiation source of the vacuum. This

  1. Increment when we move from ɣ-rays to radio waves
  2. Decrement when we move from ɣ-rays to radio waves
  3. is similar for all of them
  4. None of the above

Which of the above is correct and how?

Answer: We know that the speed of the electromagnetic wave is

Speed of light= frequency * wavelength

C= v * Λ

= 1/ µ0€0


So, here option number ‘3’ is the right answer.

Why Electromagnetic Wave Can Travel in Vacuum?

The propagation of electromagnetic waves is due to reciprocal changes in the electric and magnetic fields. And this expansion is through a vacuum. According to the famous researcher Maxwell’s equation, spatial variation in the electric field always occurs during the change in the magnetic field and spatial variation in the magnetic field always occurs during the change in the electric field.

From this, anyone can conclude that mutual variations in both electrical and magnetic fields are driven by the energy of the EM wave. So the electromagnetic wave can travel through the vacuum as long as there is no obstruction.

What Wave Can Travel in a Vacuum?

There is no doubt that electricity can be as stable as energy. Again the magnetism can also be fixed as it resides in the magnet of a refrigerator. One variable magnetic field affects another variable electric field. Due to their variability, they form electromagnetic waves.

Both electromagnetic waves and mechanical waves differ from one to another. Because it does not take any medium to propagate mechanical waves. This means that only electromagnetic waves can travel through space without air and solid matter.

Moreover, the actual speed of the electromagnetic wave depends somewhat on the optical density of that medium. This is because various material exploitation and redemption processes delay time. Even the atoms of those materials are more closely bound. This creates a short distance between their atoms. The above two factors depend on the nature of the elements and through which electromagnetic waves are traveling.

What Wave Can’t Travel in a Vacuum?

In a word, the answer will be a mechanical wave. A mechanical wave is a wave that is unable to flow or transport its energy through a vacuum. Its waves need a medium to transport them so that they can transmit their energy from one place to another. Unfortunately, this is not possible in this case. For this mechanical wave cannot travel through the vacuum.


To know the speed of an electromagnetic wave in a vacuum, you need to have a clear idea about its propagation. And there is no need for any medium to complete its propagation. So electromagnetic waves can easily travel through the outer space of a vacuum. Protection Status
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