Hur hade du tänkt att driva denna lampa? Med ett par vanliga AA-batterier du köpt på Ica?
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Ursprungligen postat av
Gubbelisa
Hur många lumens har Solen förresten?
Hittade ett svar på det på ett annat forum, kan inte säga om det är rätt eller inte men det kanske ger dig en fingervisning om vad det handlar om i siffror.
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Once we know how bright the sun is in lux directly overhead, we can use that number to figure the lumens (since the sun radiates more or less equally in all directions.
Digging around, I found that bright sunlight is 50K-100K lux. Let's go halvies on that, and say 75K lux.
That answers one of your questions.
Now, lux is defined as lumens per square meter. So, we are measuring 75,000 lumens per square meter at the Earth's surface. All we have to do is find the number of square meters on the surface of a sphere with a radius equal to the Earth's distance from the sun.
The Earth is about 150 million km from the sun (150 billion meters). The formula for the area of a sphere of radius r is 4(pi)r^2.
Thus, the sphere has a surface area of 4(pi)(150x10^9)^2 = 2.83*10^23 square meters.
Multiply that by the lux value from before (75,000 lux = 75,000 lumens/m^2) and we get 2.12x10^28 lumens.
)backs hjälp..
