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Spherical balls of radius R are falling in a viscous fluid of viscosity η with a velocity v. The retarding viscous force acting on the spherical ball is

directly proportional to R but inversely proportional to v.

inversely proportional to both radius R and velocity v.

inversely proportional to R but directly proportional to velocity v.

Fluid Mechanics

JEE Main level, single correct, medium

192 of 192

Question 192 of 192

Spherical balls of radius $R$ are falling in a viscous fluid of viscosity $\eta$ with a velocity $v$ . The retarding viscous force acting on the spherical ball is

Show answer and solution

Answer: (B) directly proportional to both radius $R$ and velocity $v$ .

Retarding viscous force

=6 \pi \eta \mathrm{R} v

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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More Physics practice

JEE Main Physics practice question on Fluid Mechanics (Viscosity), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

Spherical balls of radius RRR are falling in a viscous fluid of viscosity η\etaη with a velocity vvv. The retarding viscous force acting on the spherical ball is

JEE Main question paper PDF

More Physics practice

Spherical balls of radius $R$ are falling in a viscous fluid of viscosity $\eta$ with a velocity $v$ . The retarding viscous force acting on the spherical ball is