Physics · 2025
JEE Main · 7 April 2025, Shift 2 · Q40
A mirror is used to produce an image with magnification of 1/4. If the distance between object and its image is 40 cm, then the focal length of the…
A mirror is used to produce an image with magnification of $\displaystyle \frac{1}{4}$. If the distance between object and its image is $\displaystyle 40$ cm, then the focal length of the mirror is $\displaystyle \_\_\_\_$.
Official answer
From NTA’s final answer key for this paper.
(2)
10.$\displaystyle 7$ cm
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.