Use the concept the viscous force is the same as the weight of the body,
⇒F=mg=ρ×(34πr3)×g=3.9×10−10N.
In Millikan's oil drop experiment, what is viscous force acting on an uncharged drop of radius 2.0×10−5m and density 1.2×103kgm−3? Take viscosity of liquid =1.8×10−5Nsm−2. (Neglect buoyancy due to air).
Held on 27 Aug 2021 · Verified 6 Jul 2026.
5.8×10−10N
3.9×10−10N
1.8×10−10N
3.8×10−11N
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