What happens to projected light after the source stops

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SUMMARY

When a flashlight or laser is turned off, the projected light is absorbed by surrounding objects. The energy from the light is transferred to the atoms it encounters, which may then release that energy in various forms such as light or heat. Given that light travels at 300,000 km/s, the last photons emitted continue moving away almost instantaneously, making it impossible for the light to "stick around" after the source is turned off.

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AMan24
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Let's say a flashlight or a laser is turned on and there's light coming out of it. Once you turn the flashlight or laser off what exactly happens to the projected light? Obviously it won't be visible anymore, but where does it go?
 
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Simply put, it's absorbed by the objects surrounding it.
 
mrnike992 said:
Simply put, it's absorbed by the objects surrounding it.

Ok now I get it. Thanks
 
The energy of the light is transferred to the atoms it comes in contact with, if it does... they then might pass on that energy in different ways. light, heat, etc.
 
Perhaps the light gets absorbed, perhaps not. Remember, light travels at 300,000 km / sec, so who's to say the light sticks around to get absorbed? By the time you'd notice the beam is shut off, the last photons have almost reached the orbit of the moon. :wink: :eek:
 

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