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Ray Optics — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsRay Optics1 Mark
Question

Missing lines in a continuous spectrum reveal

(a) Defects of the observing instrument

(b) Absence of some elements in the light source

(c) Presence in the light source of hot vapours of some elements

(d) Presence of cool vapours of some elements around the light source
✓

Answer

(d) Presence of cool vapours of some elements around the light source

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