If two thin lenses of focal lengths f1,f2 are placed in contact coaxially, then equivalent focal length of combination is F1=f11+f21−f1f20=f11+f21 Power for the combination is P=F1=f11+f21=f1f2f1+f2
Two thin lenses of focal lengths f_1 and f_2 are in contact and coaxial. The power of the combination is
NEET UG 2008 — Physics Optics
2008mcqeasy
Two thin lenses of focal lengths f1 and f2 are in contact and coaxial. The power of the combination is
Official previous-year question
Held on 30 Apr 2008 · Verified 9 Jul 2026.
Options
- A
f2f1
- B
f1f2
- C
f1f2f1+f2
- D
f1f2f1+f2
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