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Electromagnetic radiation (EMR) is a form of radiated or transported energy that does not require a medium in order to propagate, unlike mechanical waves such as sound and vibrations. Mechanical waves travel by transferring energy through molecular contact, causing molecules to bump into each other in order to transfer kinetic energy which can be observed visually in water ripples. Electromagnetic waves are created by magnetic and electric fields coupling together to form waves, usually released by certain electromagnetic processes. The most common examples of electromagnetic radiation are visible light and X-rays.
Electromagnetic radiation is also known as electromagnetic waves.
Electromagnetic radiation is energy emanated radially, formed through the combined vibration of electrical and magnetic fields. This type of energy does not require a medium in order to propagate, meaning that it can travel in the vacuum of space, unlike sound which requires matter such as air in order to propagate. The electric and magnetic fields that comprise an electromagnetic wave are perpendicular to each other in the direction that the wave is traveling, and it travels at the speed of light until it interacts with substantial matter or objects which may interfere with its propagation, such as concrete or metal.
Electromagnetic radiation or energy can be described through three properties:
James Clerk Maxwell was the first scientist to postulate the existence of electromagnetic radiation/waves. He developed a scientific theory and equations to explain electromagnetic radiation and then summarized the relationship between magnetism and electricity into what are known as the Maxwell equations. Heinrich Hertz later confirmed Maxwell's theories and then applied them to the reception and production of electromagnetic waves.