2007-08-30 18:03:57 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Physics
LUX is a measurement of the light intensity falling on a surface.
A typical 18w CFL bulb may deliver 1800 lumens (equiv. 75w incandescent)
If ALL this light was focussed onto a single surface of 1 sq. meter, then it would produce an illumination of 1800 Lux.
So to solve this you need to know the 'Lumen' rating of your bulbs PLUS the distance from the bulbs to the surface to be measured ...
Heres a quick 'back of the envelope' calculation ..
Replace all your existing incandescent bulbs with the CFL equivalent rating (so, if your classromm has 20 x 100w bulbs, you will need 27 x (75w equiv) CFL bulbs)
(see also second reference .. ambient temp and bulb orientation also effect light output)
2007-08-30 21:29:05 · answer #1 · answered by Steve B 7 · 0⤊ 0⤋
Adding to the answers do not forget that the intensity of the light is inversely proportional to the square of the distance from the source to the receiving object or something like that so you need a lot more information.
2007-09-01 18:59:35 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Compact Fluorescent Light Bulbs are not known for their brightness but for their low energy consumption.
Most of them start at 40W and really the amount of light they produce can vary from one manufacturer to another.
I suggest you find the right bulb and read the specification and do the division yourself.
2007-08-31 08:12:37 · answer #3 · answered by Anonymous · 0⤊ 0⤋
question is incomplete without the altitude and the lights position.
2007-09-02 14:05:52 · answer #4 · answered by mohan 2 · 0⤊ 0⤋