Where does light go?

[lewcos]

If you shine a flashlight into a mirror - it reflects towards whatever the mirror is pointing at.<br /><br />If we made a room full of mirrors and turned on a flashlight, why would'nt the light continue reflecting after the flashlight was turned off?<br /><br />Does it lose some of its "power" upon reflection?<br /><br />If we found a substance that light could not penetrate, couldn't we turn on a light and let it keep bouncing off the walls to keep the room illuminated?

 

[Saiph]

<i>if</i> the mirrors were perfect, it will continue to do so.<br /><br />However, they aren't. As such a small amount is absorbed by the mirror, and re-radiated as another color...or sets the atoms vibrating and moving, increasing their temperature.<br /><br />So the energy of light gets turned into heat in a non-perfect system. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[Leovinus]

The mirrors are not perfect reflectors. Some of the energy is absorbed with each reflection. <div class="Discussion_UserSignature"> </div>

 

[lewcos]

"if the mirrors were perfect, it will continue to do so. "<br /><br />Can there be "perfect" mirrors? At least perfect enough to keep reflecting the light for any sustained period of time?

 

[larper]

Even if the mirrors were perfect, and the light reflected forever, the room would remain "dark", ie, you couldn't see the light. If you actually did see the light, that meant the photons were being scattered, and again, eventually (rather quickly actually), the room would go dark again. <div class="Discussion_UserSignature"> <p><strong><font color="#ff0000">Vote </font><font color="#3366ff">Libertarian</font></strong></p> </div>

 

[Saiph]

well, the act of seeing the light absorbs them...so there ya go.<br /><br />Light has been trapped for indefinite periods of time (IIRC) in a specially designed crystal that acted as a perfect mirror for certain wavelengths. The light would undergo complete internal reflection (principle behind fiber optic cables) off of every facet. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>