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Ray Optics — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsRay Optics1 Mark
Question

When light rays from the sun fall on a convex lens along a direction parallel to its axis

(a) Focal length for all colours is the same

(b) Focal length for violet colour is the shortest

(c) Focal length for yellow colour is the longest

(d) Focal length for red colour is the shortest
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Answer

(b) Focal length for violet colour is the shortest

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