Physics · 2021
JEE Main · 25 February 2021, Shift 1 · Q28
The same size images are formed by a convex lens when the object is placed at 20 cm or at 10 cm from the lens. The focal length of convex lens is \ \…
The same size images are formed by a convex lens when the object is placed at $\displaystyle 20$ cm or at $\displaystyle 10$ cm from the lens. The focal length of convex lens is \_\_\_\_ cm.
Official answer
15
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.