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A photographic camera with a lens of focal length 5 cm is used for capturing images. The vertical length of the film used is 24 mm in which image of a 1 . 68 m tall man is to be captured. Find the minimum distance (in m ) of the man from the lens such that his complete image can be obtained.

Correct answer

3.55

Step-by-step solution

The lens of a camera is convex and the image is inverted m = h i h o = - 24   m m 1.68   m = - 1 70 m = f f + u = - 1 70 70 f = - f - u - u = 71 f = 355   cm = 3 . 55   m

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