Question

Which of the following sentence is incorrect?
1. A lens has two focal points
2. The distance between focas and optic centre is
" known as focal length
3. The mid point of a thin lens is called optic centre of lens
4. A lens has two radii of curvature
5.All the above​

Answer 1

Step-by-step explanation:

The mid point of a thin lens is called optic centre of lens

this is incorrect