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Ray Optics

JEE Main level, single correct, medium

144 of 295

Question 144 of 295

Two identical symmetric double convex lenses of focal length $f$ are cut into two equal parts $L_1, L_2$ by $A B$ plane and $L_3, L_4$ by $X Y$ plane as shown in figure respectively. The ratio of focal lengths of lenses $L_1$ and $L_3$ is

Show answer and solution

Answer: (B) 1:2

\frac{f_1}{f_3}=1: 2

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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More Physics practice

JEE Main Physics practice question on Ray Optics (Lens Formula, Refraction of light from curved surface), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

Two identical symmetric double convex lenses of focal length fff are cut into two equal parts L1,L2L_1, L_2L1​,L2​ by ABA BAB plane and L3,L4L_3, L_4L3​,L4​ by XYX YXY plane as shown in figure respectively. The ratio of focal lengths of lenses L1L_1L1​ and L3L_3L3​ is

JEE Main question paper PDF

More Physics practice

Two identical symmetric double convex lenses of focal length $f$ are cut into two equal parts $L_1, L_2$ by $A B$ plane and $L_3, L_4$ by $X Y$ plane as shown in figure respectively. The ratio of focal lengths of lenses $L_1$ and $L_3$ is