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

Question

Spherical balls of radius R are falling in a viscous fluid of viscosity n with a velocity v. The retarding viscous force acting on the spherical ball is (A) directly proportional to R but inversely proportional to v (B) directly proportional to both radius R and velocity v (C) inversely proportional to both radius R and velocity v (D) inversely proportional to R but directly proportional to velocity v

Tardigrade Admin · Accepted Answer

Retarding force acting on a ball falling into a viscous fluid F=6π η Rv where R= radius of ball, v= velocity of ball and η = coefficient of viscosity ∴ F propto R and F propto v Or in words, retarding force is directly proportional to both R and v .

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

directly proportional to R but inversely proportional to v

directly proportional to both radius R and velocity v

inversely proportional to both radius R and velocity v

inversely proportional to R but directly proportional to velocity v

Retarding force acting on a ball falling into a viscous fluid $F = 6 π η R v$ where $R =$ radius of ball, $v =$ velocity of ball and $η =$ coefficient of viscosity $∴$ $F \propto R$ and $F \propto v$ Or in words, retarding force is directly proportional to both $R$ and $v$ .

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

directly proportional to R but inversely proportional to v

directly proportional to both radius R and velocity v

inversely proportional to both radius R and velocity v

inversely proportional to R but directly proportional to velocity v

Retarding force acting on a ball falling into a viscous fluid F=6πηRv where R= radius of ball, v= velocity of ball and η= coefficient of viscosity ∴ F∝R and F∝v Or in words, retarding force is directly proportional to both R and v .

Retarding force acting on a ball falling into a viscous fluid $F = 6 π η R v$ where $R =$ radius of ball, $v =$ velocity of ball and $η =$ coefficient of viscosity $∴$ $F \propto R$ and $F \propto v$ Or in words, retarding force is directly proportional to both $R$ and $v$ .