Question

18. A ray passing through ........ of a convex lens will take a path parallel to principal axis
after refraction.
[ ]
A) centre of curvature
B) focus
C) pole
D) parallel to principal axis​

Answer 1

a ray of light going along the path of principal axis of a convex lens also goes straight and does not deviate. Rule 3: When a ray of light passes through the focus of the convex lens then it becomes parallel to the principal axis after refraction through the lens.