Physics · 2021
JEE Main · 27 August 2021, Shift 1 · Q1
In Millikan's oil drop experiment, what is viscous force acting on an uncharged drop of radius 2.0 × 10^-5 m and density 1.2 × 10^3 kgm^-3? Take…
In Millikan's oil drop experiment, what is viscous force acting on an uncharged drop of radius $\displaystyle 2.0 \times 10^{-5} \mathrm{~m}$ and density $\displaystyle 1.2 \times 10^3 \mathrm{kgm}^{-3}$ ? Take viscosity of liquid $\displaystyle =1.8 \times 10^{-5} \mathrm{Nsm}^{-2}$. (Neglect buoyancy due to air).
Official answer
(4)
$\displaystyle 3.9 \times 10^{-10} \mathrm{~N}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.