f1=(μg−1)R2=R1,(μg=23)⇒R=f
f11=−(μw−1)R2=3R−2=3f−2.
feq1=f1+f1+f11=R1+R1−3R2
feq1=f1+f1−3f2
feq1=f2−3f2
feq1=3f4
feq=43f.
Two identical glass (μ _g= 3 2) equiconvex lenses of focal length, f are kept in contact. The space between the two lenses is filled with water (μ…
NEET UG 2016 — Physics Optics
2016mcqhard
Two identical glass (μg=23) equiconvex lenses of focal length, f are kept in contact. The space between the two lenses is filled with water (μw=34). The focal length of the combination is
Official previous-year question
Held on 30 Apr 2016 · Verified 9 Jul 2026.
Options
- A
3f
- B
f
- C
34f
- D
43f
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