JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
Two thin convex lenses of focal length 30 cm and 10 cm are placed coaxially, 10 cm apart. The power of this combination is :
- A 5 D
- B 1 D
- C 20 D
- D 10 D
Answer & Solution
Correct Answer
(D) 10 D
Step-by-step Solution
Detailed explanation
\(\mathrm{f}_1=30 \mathrm{~cm}, \mathrm{f}_2=10 \mathrm{~cm}\) \(\frac{1}{\mathrm{f}_{\mathrm{eq}}}=\frac{1}{\mathrm{f}_1}+\frac{1}{\mathrm{f}_2}-\frac{\mathrm{d}}{\mathrm{f}_1 \mathrm{f}_2}, \mathrm{~d}=\) distance between lens…
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