When refractive index of lens is equal to the refractive index of liquid, the lens behave like a plane surface with focal length infinity.
A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens. Then its focal length will:
NEET UG 2003 — Physics Optics
2003mcqeasy
A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens. Then its focal length will:
Official previous-year question
Held on 30 Apr 2003 · Verified 9 Jul 2026.
Options
- A
become zero
- B
become infinite
- C
become small, but non-zero
- D
remain unchanged
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