Light Intensity at Point Sources: Impact on Energy Falloff?

AI Thread Summary
Light intensity at a point source significantly affects how energy falls off, adhering to the inverse square law. If two sources emit equivalent intensity, the energy received at a given distance will be the same. In the example of replacing the sun with billions of candles to match its brightness, the appearance would be similar at a distance like Pluto, provided the observer is far enough away. Close proximity to the sources may reveal differences in light quality or distribution. Overall, distance and intensity are crucial in determining perceived energy levels from light sources.
djmike
Messages
7
Reaction score
0
i am a little confused as to whether light intensity at a point source is critical to how the energy will fall off(i know inverse sq ). if there is equivalent intensity from 2 sources will there be the same energy at any given distance?

sorry if that is a little convoluted... here is a more specific example...

if the sun was replaced by billions of candles so it was as bright as the normal sun here on earth, would it still look the same as the sun would furthor away, say on pluto??
 
Science news on Phys.org
Essentially yes. Only if you are close could there be a signigficant difference between the two cases.
 
Thread 'A quartet of epi-illumination methods'
Well, it took almost 20 years (!!!), but I finally obtained a set of epi-phase microscope objectives (Zeiss). The principles of epi-phase contrast is nearly identical to transillumination phase contrast, but the phase ring is a 1/8 wave retarder rather than a 1/4 wave retarder (because with epi-illumination, the light passes through the ring twice). This method was popular only for a very short period of time before epi-DIC (differential interference contrast) became widely available. So...
I am currently undertaking a research internship where I am modelling the heating of silicon wafers with a 515 nm femtosecond laser. In order to increase the absorption of the laser into the oxide layer on top of the wafer it was suggested we use gold nanoparticles. I was tasked with modelling the optical properties of a 5nm gold nanoparticle, in particular the absorption cross section, using COMSOL Multiphysics. My model seems to be getting correct values for the absorption coefficient and...
Back
Top