The focal length of a convex lens is f L =10 cm. On immersing in water, it…
2023
The focal length of a convex lens is f L =10 cm. On immersing in water, it will act as a
- A.
convex lens of f L =10 cm
- B.
concave lens of f L =10 cm
- C.
convex lens of F L >10 cm
- D.
More than one of the above
- E.
None of the above
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Correct answer: C
When a convex lens is immersed in water, its focal length increases because the refractive index difference between the lens material and surrounding medium decreases. Since water has a higher refractive index than air, the lens's converging power reduces, resulting in a longer focal length. Therefore, it still acts as a convex lens but with fL > 10 cm.