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प्रश्न
How are electromagnetic waves produced?
उत्तर
Moving charges produce electric and magnetic field waves, which are then combined to form electromagnetic waves. All electromagnetic waves originate from charged particles. An electric field produced by this charged particle can act as a force on other adjacent charged particles. The charged particle produces a magnetic field and ripples or oscillations in its electric field as it accelerates as part of an oscillatory motion, as predicted by Maxwell's equations. Once a charged particle is in motion, the electric and magnetic fields it generates are self-replicating, with changes in either field (electric or magnetic) causing changes in the other. An electromagnetic wave's electric and magnetic fields will both vary over time, with one influencing the other. Any time a charged particle experiences a change in velocity, electromagnetic waves (photons) are generated. Energy is conserved via the electromagnetic wave (radiation) that is created when the charged particle changes its velocity. Light makes up this energy. Microwave oven manufacturing is a straightforward illustration of this. A magnetron is a part found within a microwave. A cavity that functions as an electron racecourse is located inside the magnetron. The electrons move extremely quickly over this little circular track. The electrons are moving back and forth towards the inside and outside of the racing track while they are moving at these extremely high speeds and in little circles. Microwaves are produced as a result of this high-frequency wriggling.
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