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JEE PHYSICS MCQ: RAY OPTICS

1 Medium

1 of 1

Application +4 | -1

With a concave mirror, an object is placed at a distance

{x_1}

from the principal focus, on the principal axis. The image is formed at a distance

{x_2}

from the principal focus. The focal length of the mirror is

View answer and explanation

Correct option: D

\sqrt {{x_1}\,{x_2}}

Option D (

\sqrt {{{{x_1}}}\,{{{x_2}}}} }

) is correct because it represents Newton's mirror formula, relating object and image distances from the focus to the focal length.

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