Mechanical Properties of Fluids
Class 11 · Mechanical Properties of Fluids

Stokes' Law

F_drag = 6πηrv — viscous drag on a sphere through fluid.

Run simulation

Key Notes

01

A small sphere of radius r moving slowly through a viscous fluid experiences drag F = 6πηrv.

02

Valid for low Reynolds numbers (smooth, laminar flow).

03

Drag is linear in v — unlike high-speed drag (∝ v²).

Formulas

Stokes drag

Spherical object, slow flow.

Important Points

Used to determine viscosity (Stokes' viscometer).

Used in Millikan oil-drop experiment to measure electron charge.

Stokes' Law notes from sciphylab (also known as SciPhy, SciPhy Lab, SciPhy Labs, Physics Lab). Class 11 physics revision for JEE Mains, JEE Advanced, NEET UG, AP Physics 1/2/C, SAT, and CUET-UG.