Which of the following point(s) always lie(s) on the principal axis of a lens? (i) Point of refraction (ii) Optical Centre (iii) Point of incidence

Correct option is C

​The correct answer is (c) Only (ii)

Explanation: The optical center always lies on the principal axis of a lens.

Information Booster: 

• The optical center is the point in a lens where light rays passing through it either remain undisturbed or are not deviated by the lens. In simple terms, it is the point through which light can pass without being bent.
• The principal axis is the straight line that passes through the optical center and is perpendicular to the lens surfaces.
• It is the main reference line used in ray diagrams to study the behavior of light as it passes through the lens.