Relation between intensity of Sun and the light that is emitted from surface of sun please correct me if I am mistaken, I was in the middle of a thought process. We take a unit area dA of sun,, which is emitting light directly to our line of sight. But there are also numerous other unit areas throughout sun's surface whose light does not reach our eyes directly. Then why do we still see the sun with same intensity?
We take a unit area dA of sun,, which is emitting light directly to our line of sight


You are, I think, imagining the light as if it was directed out from a point, with directions of photons outward from the center.

What actually happens is that the light is emitted from every point on the surface and what's more every point on the surface can send light in any and all directions.

So the Sun is a diffuse source of light, not a point source of light.


  But there are also numerous other unit areas throughout sun's surface whose light does not reach our eyes directly.


So because of what I have described - light being emitted in all possible directions from all over the Sun's surface - we do see light from all parts of the surface.  And that light does reach our eyes directly.