Because when you pour batter into the pan, the batter diffuses, or spreads out. While cooking, it thins and the edges are thinnest because diffusion isn't done finding a balance. The middle is still thicker because of the process of diffusion isn't done, so it will be thicker in middle naturally.
Hope this helps! :-)
thicker at the edges that in the middle
The edges of a convex lens are thicker than the middle.
Concave. The opposite- thick in middle, thin at edges- is convex.
thicker, thinner
thicker at the edges that in the middle
Concave
no
CONCAVE lens.
A Convex Lens
They can be either. They will converge if thicker in the middle than edges, and diverge if thinner in the middle than edges.
Concave lens
It is called a convex lens.