Question

A sphere of density ρ & mass m is moving down with constant velocity in viscous liquid of density ρ0. Find out viscous force on sphere

• A. $mg(\frac{1-\rho _{0}}{\rho})$
• B. $2mg(\frac{1-\rho _{0}}{\rho})$
• C. $mg(\frac{1-3\rho _{0}}{\rho})$
• D. $mg(\frac{1+\rho _{0}}{\rho})$

Answer 1

Answer: (A)

$mg(\frac{1-\rho _{0}}{\rho})$

Answer 2

F=mg-Fb
F=mg-ρ0$\frac{mg}{rho}$
F=mg($\frac{1-\rho_{0}}{\rho}$)

So, the correct answer is (A): $mg(\frac{1-\rho _{0}}{\rho})$