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JEE PHYSICS MCQ: RAY OPTICS

1 Medium

1 of 1

Application +4 | -1

A screen is placed

90\, {~cm}

from an object. The image of an object on the screen is formed by a convex lens at two different locations separated by

20\, {~cm}

. The focal length of the lens is

View answer and explanation

Correct option: B

21.4\, {~cm}

Option B (

21.4\, {~cm}

) is correct because it uses the displacement method formula to calculate the focal length of the convex lens.

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