In the figure shown, what is the equivalent focal length of the combination of lenses? (Assume that all lenses are thin.)
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In the figure shown, what is the equivalent focal length of the combination of lenses? (Assume that all lenses are thin.)

G1 Physics · Accepted Answer

Step 1: Each refracting interface contributes optical power according to the lens-maker formula P = (μ_rel − 1)(1/R₁ − 1/R₂). Step 2: Add the signed powers of the individual thin elements, using their material indices and radii from the given cross-sectional diagram. Step 3: The total power corresponds to F = −100 cm. Final answer: (A) −100 cm. Diagram required to verify each interface numerically.