Physics · 2021
JEE Main · 27 July 2021, Shift 1 · Q11
Two identical tennis balls each having mass ' m ' and charge ' q ' are suspended from a fixed point by threads of length ' l '. What is the…
Two identical tennis balls each having mass ' m ' and charge ' q ' are suspended from a fixed point by threads of length ' $\displaystyle l$ '. What is the equilibrium separation when each thread makes a small angle ' $\displaystyle \theta$ ' with the vertical ?
Official answer
(2)
$\displaystyle x=\left(\frac{\mathrm{q}^2 l}{2 \pi \varepsilon_0 \mathrm{mg}}\right)^{1 / 3}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.