EM Wave Creation and Physical Characteristics

In summary, the conversation discusses the creation and physical nature of electromagnetic waves. It is mentioned that EM-waves are created by accelerated charges and that a charge moving with constant velocity may also have a similar effect. The discussion also touches on the concept of electrons exciting and dropping down to their ground state, resulting in the release of energy in the form of photons. These photons have both wave and particle characteristics and are responsible for the energy and frequency of the electromagnetic wave. Ultimately, the electromagnetic wave is described as a transverse wave comprised of oscillating E and B fields, with the frequency and wavelength of the wave being inversely proportional to each other.
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My book seems to not go into a lot of details as to how EM-waves are created. More or less they just state that they are created by accelerated charges. I guess that somehow makes sense since an accelerated charge is clearly altering the electric field everywhere in space and that is as far as I can see what creates an electromagnetic disturbance -> electromagnetic wave. But shouldn't a charge moving with constant velocity do the same? And what is an electromagnetic physically? Is it information about the altering of the field spreading out or..
 
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Electrons exciting and dropping down to their ground state. The energy that was held by the electron in its excited state needs to go somewhere when the electron jumps back down to its ground state and is released as a packet of energy. This energy is called "quanta" and was latter called a photon. These photons have particle-wave duality (meaning they have characteristics of waves and particles) They act like particles to an extent because we can count them with photo multipliers, but they have wave like properties as well.

What is a electromagnetic wave (physically)?
So under the wave model,
The EM wave is a Transverse wave meaning the wave oscillations are perpendicular the direction of the energy. The EM wave physically is an wave comprised of E and Bfields oscillating in phase perpendicular to each other (where the E field is the bigger of the two) where the frequency of the wave is inversely proportional to the wave length
v=fλ​

If you were to look at the wave from a particle standpoint:
Quanta released from the electrons (Dubbed Photons by Einstein) would be propagated and would have a energy porportional to its frequency by this formula:
E=hf=hc/λ​

Hope this helps!
 
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What creates EM waves?

EM waves are created by the acceleration of charged particles, such as electrons, in a changing magnetic or electric field. This acceleration produces a disturbance in the electric and magnetic fields, which propagates through space as an electromagnetic wave.

How are EM waves different from other types of waves?

EM waves are characterized by their ability to travel through a vacuum, unlike mechanical waves which require a medium to travel through. They also have a wide range of wavelengths and frequencies, from long radio waves to short gamma rays.

What are the sources of EM waves on Earth?

The majority of EM waves on Earth are created by human activities, such as radio and television broadcasts, cell phones, and radar systems. Natural sources include lightning, the sun, and other celestial bodies.

Do EM waves have any harmful effects on living organisms?

EM waves with high frequencies, such as X-rays and gamma rays, can be harmful to living organisms as they have enough energy to ionize atoms and damage DNA. However, the low frequency EM waves, such as radio waves, are not known to have any harmful effects on living organisms.

What are some practical applications of EM waves?

EM waves have a wide range of practical applications, including communication systems such as radio and television, medical imaging techniques like MRI, and remote sensing technologies used in weather forecasting and navigation systems.

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