Focal length of lens f1=25 cm focal length of concave lens f2=25 cm Power of combination in dioptres P=P1+P2=f1100+f2100=25100+−25100=0.
A convex lens and a concave lens, each having same focal length of 25 ~cm, are put in contact to form a combination of lenses. The power in diopters…
NEET UG 2006 — Physics Optics
2006mcqeasy
A convex lens and a concave lens, each having same focal length of 25 cm, are put in contact to form a combination of lenses. The power in diopters of the combination is:
Official previous-year question
Held on 30 Apr 2006 · Verified 9 Jul 2026.
Options
- A
zero
- B
25
- C
50
- D
infinite
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