Question

a real image of twice the size of the object is formed at a distance of 42 cm on other side of a convex lens find the object distance and the focal length of lens

Answer 1

Answer:

To form an image twice the size of the object, using a convex lens of focal length 20 cm, the object distance must be – ... < 20 cm and between 20 cm and 40 cm.

Explanation:

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