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Grade Select GradeGeneral Physics

A biconvex lens of focal length f forms a circular image of sun of radius r in focal plane. Then (A) ?r2 œ f (B) ?r2 œ f2 (C) if lower half part is covered by black sheet, then area of the image is equal to ?r2/2 (D) if f is doubles, intensity will increase please clearify!!!!!! A biconvex lens of focal length f forms a circular image of sun of radius r in focal plane. Then (A) ?r2 œ f (B) ?r2 œ f2 (C) if lower half part is covered by black sheet, then area of the image is equal to ?r2/2 (D) if f is doubles, intensity will increase A biconvex lens of focal length f forms a circular image of sun of radius r in focal plane. Then (A) ?r2 œ f (B) ?r2 œ f2 (C) if lower half part is covered by black sheet, then area of the image is equal to ?r2/2 (D) if f is doubles, intensity will increase A biconvex lens of focal length f forms a circular image of sun of radius r in focal plane. Then (A) ?r2 œ f (B) ?r2 œ f2 (C) if lower half part is covered by black sheet, then area of the image is equal to ?r2/2 (D) if f is doubles, intensity will increase

Profile image of Rahbar Ahmad
16 Years agoGrade Select Grade
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Profile image of Aryan raj
8 Years ago
After reflection from biconvex lens image will form at the focus ,since light rays are comming from very far distace . A convering image will form at focus of biconvex lens A triangle is formed , sotanϴ= r/fF×tanϴ=rF ∝rF^2∝πr^2R^2∝f^2