The intensity of light drops off with the square of the distance. So if your
lamp is 3 feet away, the light will be 1/9 of the intensity than at 1 foot,
and so on.
BFN
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| John Taylor [The Banshee] | Royal Melbourne Institute of Technology |
| rphjt@minyos.xx.rmit.oz.au | Department of Applied Physics |
| MOKING IS A HEALTH HAZARD. | Melbourne, Victoria, AUSTRALIA |
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