Physics · 2021
JEE Main · 27 July 2021, Shift 1 · Q16
The figure shows two solid discs with radius R and r respectively. If mass per unit area is same for both, what is the ratio of MI of bigger disc…
The figure shows two solid discs with radius $\displaystyle R$ and $\displaystyle r$ respectively. If mass per unit area is same for both, what is the ratio of MI of bigger disc around axis AB (which is ⟂ to the plane of the disc and passing through its centre) to MI of smaller disc around one of its diameters lying on its plane ? Given 'M' is the mass of the larger disc. (MI stands for moment of inertia)
Official answer
(3)
$\displaystyle 2 \mathrm{R}^4: \mathrm{r}^4$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.