Physics · 2022
JEE Main · 28 July 2022, Shift 1 · Q46
In normal adujstment, for a refracting telescope, the distance between objective and eye piece is 30 cm. The focal length of the objective, when the…
In normal adujstment, for a refracting telescope, the distance between objective and eye piece is $\displaystyle 30$ cm. The focal length of the objective, when the angular magnification of the telescope is $\displaystyle 2$ , will be :
Official answer
(1)
$\displaystyle 20$ cm
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JEE Main 2022 Physics question, with the answer from NTA’s final answer key. Where our answers come from.