What is the typical light intensity coming out of a 200 Watt-220V electric lamp with tungsten filament, while it's operated at 220Volt. Please let me know the intensity in mW/cm2 unit or lux unit.
here is a nice paper
http://www.radiance-online.org/community/workshops/2004-fribourg/presentations/Wandachowicz_paper.pdf
Typically one doesn't talk about the intensity of a source because intensity is an amount of power delivered to a certain area, meaning that intensity is dependent not just on the brightness of a source but also on things like the distance away from the source, the amount of power collected (i.e. by collecting lens of a certain size at a certain distance, for example) from the source and delivered to the region of interest, the focal length/focal spot of the collecting optic, etc. This is why a previous responder's answer was in lumens, which is a unit measuring the "luminous power" (visible light energy emitted per time from a source) of a source, rather than in mW/cm2 as requested.
200 W of capacity of a lamp extend in a space angle 4*3.14. The irradiance at R distance from a lamp makes 200 (/4*3,14*R^2) W/cm2
Thank you all of you for your answers.
I would like to ask Mr. Pavan Pagre, what lux meter was employed for the measurement?
The intensity depends on the solid angle, solid angle changes with the distance between sources and the viewer. The intensity of the moon and the sun is different, but the solid angle is the same from the earth, both the moon and the sun cover the same area on your view, so the radiance will be much much higher than the moon. So the intensity of light bulb will depend on how are you looking at the bulb and from what distance. The unit will be in w/m2/steradian
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