Question

Find the focal length of a convex lens which is used to correct the hypermetropia in the terms of distance of near point d​

Answer 1

Answer:

First, we will calculate the focal length for that lens. We know that the hypermetropic eye can see the nearby object kept at 25 cm clearly if the image of this object is formed at its own near point which is 40 cm here. Hence, we get focal length, f = 66.66 cm = 66.66100m= 0.6666m

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