Lightspeed fast, then slowed, then fast again.

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Light slows down when passing through materials like water and glass due to absorption and re-emission by the matter, but it always travels at the speed of light "c" in a vacuum. The apparent slowdown is not a loss of energy; rather, energy is conserved as light interacts with matter. When light exits a medium, it resumes its speed without needing an additional energy source. This phenomenon aligns with Newton's law of conservation of energy. The discussion clarifies that light's speed remains constant, regardless of the medium it traverses.
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I was reading material on light speed and have a question about something I thought may contradict Newtons law of conservation of energy.

Light slows down as it passes through water, glass etc.. right? But when it reaches the other side it continues at light speed. Where is it getting its energy/power supply to continue back at its normal speed? Whats happening here? :eek:
 
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It ALWAYS MOVES AT "c"...It's just that matter absorbs it & reemits it and that's why the apparent "slowdown" due to presence of matter...

Daniel.

P.S.Energy is conserved.
 
ahh, thanks.
 
it never stops moving at "c" :D just the matter makes it slow down, but the nergy is used the same :D
 
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