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1. Ralph, for another similar, but opposite issue, check Olbers' Paradox...

2. As mentioned above, the inverse square law is designed to explain how the level drops as you move away from the source. However, another factor not often mentioned is that a point source is not considered a point source until you are 1/2 the length of the source, distant from the source.

So, if you have a flash tube 2 inches long, it does not become a point source until you are 1 inch away. Closer than 1 inch it becomes a line source. With its own set of rules.

Gotta love electromagnetic radiation. It paid my bills for a lot of years.

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3. I think Zeno said it was pretty bright when he got there.

4. Look at it the other way around, not at how much more bright the light is the closer you get but how much darker the light gets the further away you go.

So standing at 0 from a point light source you are losing 1/0 (aka not even a number) and that means that the light is as bright as the energy it outputs. Move back and stand 2 away and now you are losing 1/2^2 (aka one-quarter) of the original brightness. Stand 4 away and your light is now 1/4^4 (aka one-sixteenth) lost. Etc.

5. The law of inverse squares states that at least once, any nerd in high school will be put upside down in a trash can by a football player.

6. Pretty sure the question was already answered, so I'll just my two cents... Physics loves math, but math could care less about physics.

7. You have to think of it this way Ralph, forget the point light source, forget the distances, no matter how many times you "get closer" you can never actually be at 0 because two things cannot occupy the same space at the same time, and also you will always be 1/4th (or whatever the opposite of quadruple) away from the light source ALWAYS, you will never hit 0 and will never reach the light... It's impossible.

8. Originally Posted by StoneNYC
You have to think of it this way Ralph, forget the point light source, forget the distances, no matter how many times you "get closer" you can never actually be at 0 because two things cannot occupy the same space at the same time, and also you will always be 1/4th (or whatever the opposite of quadruple) away from the light source ALWAYS, you will never hit 0 and will never reach the light... It's impossible.
Stone:

Take some university physics courses and you will find that what you say here isn't actually true.

Or for that matter, watch a few Star Trek episodes .

9. Originally Posted by MattKing
Stone:

Take some university physics courses and you will find that what you say here isn't actually true.

Or for that matter, watch a few Star Trek episodes .
My dad is a real honest to god physicist... I'll ask him tomorrow...

10. Originally Posted by StoneNYC
You have to think of it this way Ralph, forget the point light source, forget the distances, no matter how many times you "get closer" you can never actually be at 0 because two things cannot occupy the same space at the same time, and also you will always be 1/4th (or whatever the opposite of quadruple) away from the light source ALWAYS, you will never hit 0 and will never reach the light... It's impossible.
Stone, you're wrong on 2 counts: firstly politicians do it every day when they make a speech. Secondly, when you walk up to the Sun and put your light meter on the surface and take a reading. THAT is point zero. You're not interested in digging through 433 thousand miles of plasma with a shovel to get the "true" reading.

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