Why Does Light Disappear When the Source is Turned Off?

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SUMMARY

The discussion centers on the phenomenon of light disappearing instantly when a light source is turned off, contrasting it with sound, which continues to travel and echo after its source is silenced. Participants highlight that light travels at approximately 186,000 miles per second, making its cessation effectively instantaneous compared to sound, which travels at about 1,000 feet per second. The conversation also touches on the nature of photons and the complexities behind light emission, indicating a deeper inquiry into the physics of light.

PREREQUISITES
  • Understanding of basic physics concepts, particularly light and sound propagation.
  • Familiarity with the speed of light (approximately 186,000 miles per second).
  • Knowledge of photon behavior and properties.
  • Basic principles of wave mechanics and sound waves.
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  • Research the properties of photons and their role in light emission.
  • Explore the differences between electromagnetic waves and sound waves.
  • Learn about the speed of light and its implications in physics.
  • Investigate the concept of instantaneous effects in wave phenomena.
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Students of physics, educators explaining wave phenomena, and anyone interested in the fundamental principles of light and sound.

Rose Garden
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A light source emits light in all directions, and the light travels at light speed, yet when we shut off this light source, all the light rays immediately disappear. I just thought about this and it just seems so strange. When we think of a sound source, we can shut off the sound source but the sound already emitted would keep traveling and echoing. But what about light, when the light source is turned off, what happens to the photons, how can the light already emitted just disappear?
 
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One difference between light and sound is the speed. Sound in air travels about 1000 ft./sec., while light goes around 186000 miles/sec. You can hear the sound echoes because of the time it takes to die off, while for light the die off is essentially instantaneous.
 
ok there's just so much I don't know: what makes light give off light?
 
wow That question is more than just a simple question! Nice!
 

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