How to derive the Lens Formula ?
Asked by tanishqa.rathod | 13th Dec, 2015, 11:30: AM
Expert Answer:
The figure above shows that formation of a real, inverted and diminished image A’B’ of the object AB placed beyond the centre of curvature at a distance u from the convex lens. Let v be the image distance.
According to Cartesian sign convention,
Object distance (OB) = -u
Image distance (OB’) = +v
Focal length (OF1 = OF2) = +f
From geometry of figure above, right angle ΔABO and ΔA’B’O are similar.
The figure above shows that formation of a real, inverted and diminished image A’B’ of the object AB placed beyond the centre of curvature at a distance u from the convex lens. Let v be the image distance.
According to Cartesian sign convention,
Object distance (OB) = -u
Image distance (OB’) = +v
Focal length (OF1 = OF2) = +f
Answered by Yashvanti Jain | 14th Dec, 2015, 10:33: AM
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