JEE PHYSICS MCQ: RAY OPTICS

1 Medium

1 of 1

Application +4 | -1

For finding out focal length of a convex lens
using two needles by parallax method, object and
image needles are 25 cm apart. If focal length of
lens is found 6 cm then possible values of object
needle distance from lens are:

View answer and explanation

Correct option: A

10 cm and 15 cm

Option A (10 cm and 15 cm) is correct because these values satisfy the lens formula when the object and image needles are 25 cm apart and the focal length is 6 cm.

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