Physics · 2021
JEE Main · 4 August 2021, Shift 1 · Q13
Choose the correct option for the centre of mass of a uniform disc of radius ' R ' from which a circular section of radius r (2 r < R ) has been…
Choose the correct option for the centre of mass of a uniform disc of radius ' $\displaystyle R$ ' from which a circular section of radius $\displaystyle \mathrm{r}(2 \mathrm{r}<\mathrm{R})$ has been removed. The centre of the hole is at a distance ' $\displaystyle a$ ' from the centre of the disc. [Take the centre of the whole disc as the origin]
Official answer
(1)
$\displaystyle \frac{a r^2}{\left(R^2-r^2\right)}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.