Question

A ray of light becomes parallel to the principal axis after passing through a convex lens. Which of the following can be concluded regarding the incident ray?

• A. It must pass through the centre of curvature.
• B. It must pass through the focus.
• C. It must be parallel to the principal axis.
• D. It must pass through the optical centre.

Answer 1

The correct option is B It must pass through the focus.

A ray of light passing through the focus of a convex lens would become parallel to the principal axis after passing through the lens.