The sun is an actual object, around .5 degrees wide. It stays about that size the entire day.
I think, it appears smaller/bigger at times. I don't think it is always the same size, but I now that you mention it, I doubt it is as noticeable as telephone poles are. Although, the point to this thread is that the sun appears to meet the ground, for the same reason that the tops of high voltage towers appear to meet the ground or clouds, or jet planes or persistent jet trails do. In other words, it isn't because you're seeing over the edge of the earth (remember that huge drop that is supposed to be occurring) it is because of an optical illusion, illustrated by the photograph in the first post of this thread.