MVP ARCHIVE SCIENCE | PHYSICS : Electromagnetic Waves - Light and Radio Waves Are All the Same Waves
Electromagnetic Waves - Light and Radio Waves Are All the Same Waves
Light is a wave. Moreover, light is not the only special wave.
In the 1860s, James Clerk Maxwell completed equations that unified electricity and magnetism, and from that theory, he derived the existence of waves that propagate through space while electric and magnetic fields change each other. This is electromagnetic waves .
Maxwell discovered that when he calculated the speed of these waves, it matched the speed of light that had already been measured at the time.
In other words, he arrived at the conclusion that light itself is an electromagnetic wave.
Later, in 1887, the German physicist Heinrich Hertz succeeded in actually generating and receiving electromagnetic waves, and Maxwell's theory was proven by experiment.
Electromagnetic waves propagate through a vacuum at the speed of light (approximately 300,000 km/s) while the electric and magnetic fields oscillate in directions perpendicular to each other, and because they can propagate without substances like air or water, sunlight reaches the Earth even through outer space.
Electromagnetic waves change their properties depending on their wavelength and frequency, but their fundamental nature is the same.
Starting from the longest wavelength, they are continuously connected as
"Radio waves, microwaves, infrared rays, visible light, ultraviolet rays, X-rays, and gamma rays"
.
Visible light, which can be seen by the human eye, is only a tiny fraction of this vast electromagnetic spectrum.
Today, many technologies that support our society, such as radio, television, mobile phones, Wi-Fi, GPS, artificial satellites, microwave ovens, infrared cameras, medical X-rays, and astronomical observations, utilize electromagnetic waves.
The discovery of electromagnetic waves did not just reveal the true nature of light.
It opened an era in which humanity could freely utilize "invisible waves," and became the foundation supporting modern communication technology, medicine, and space development.
Basic Information
Theory proposed : James Clerk Maxwell (1860s)
Proven by experiment : Heinrich Hertz (1887)
Overview
・Waves that propagate through space as electric and magnetic fields change each other
・Propagates at the speed of light even in a vacuum
・Light is also a type of electromagnetic wave
Electromagnetic spectrum
Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, gamma rays
Main applications
・Broadcasting and telecommunications
・Wi-Fi and Bluetooth
・GPS and artificial satellites
・Radar
・Microwave ovens
・Infrared sensors
・X-ray imaging
・Space astronomy
Related themes
・Radio Technology
・Wireless Communication
・Quantum Electrodynamics
・Astrophysics (Space observation via electromagnetic waves)
Archive Point
Electromagnetic waves are an important conclusion reached by research that began with Coulomb's law and built upon Ohm's law, Faraday's law of induction, Lenz's law, electromagnetism, and Maxwell's equations .
Electricity, magnetism, and light are not separate phenomena, but rather different manifestations of the same natural laws.
This unified understanding serves as the foundation of modern physics and became the catalyst for humanity to greatly expand the possibilities of information, energy, and cosmic observation by utilizing electromagnetic waves.
