"Expansion" of Light
My question is why does light expand? Why does light get dimmer
the further away it is from the source of the light?
For the purpose of your question, light acts like a wave. (because it acts like
a wave, we can use the concept of throwing a large rock into a smooth pond to
If you throw a large rock into a smooth pond, the waves it creates will expand
outwards. Because the wavefront is constantly increasing in size, and it's not
receiving any additional energy, the energy in the wave gets spread over a
larger and larger area, thus making the wave itself much smaller in height as
In other words, you went a long ways towards answering your own question.
Light grows dimmer the further you are from it, because it is expanding. If
you were to try this with a laser, which expands far less, than the amount it
dims over distance would also decrease.
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Update: June 2012