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| Derivation of Lens Formula (Convex Lens) |
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| Let AB represent an object placed at right angles to the principal axis at a distance greater than the focal length f of the convex lens. The image A1B1 is formed beyond 2F2 and is real and inverted. |
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| OA = Object distance = u |
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| OA1 = Image distance = v |
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| OF2 = Focal length = f |
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 OAB and  OA1B1 are similar |
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| But we know that OC = AB |
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 the above equation can be written as |
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| From equation (1) and (2), we get |
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| Dividing equation (3) throughout by uvf |
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