Question

Difference between concave and convex lens

Answer 1

convex

1.Convex lenses are thicker at the middle.
2.Rays of light that pass through the lens are spread out (they diverge). 

concave.

1.a concave lens thinner at it's centre.
2.A concave lens is a lens that possesses at least one surface that curves inwards.

Answer 2

In a convex lens, both the surface are convex. The convex lens is thicker at the centre than at the edges. Since the image can be captured on screen, it is a real image. where as, a concave lens is thinner at he centre than at edges. A concave lens does not form a real image.