Question: The viscous drag acting on a metal sphere of diameter $1 \mathrm{~mm}$, falling through a fluid of viscosity $0.8 \mathrm{~Pa} \mathrm{~s}$ with a velocity of $2 \mathrm{~m} \mathrm{~s}^{-1}$ is equal to :
A) $15 \times 10^{-3} \mathrm{~N}$
B) $30 \times 10^{-3} \mathrm{~N}$
C) $1.5 \times 10^{-3} \mathrm{~N}$
D) $20 \times 10^{-3} \mathrm{~N}$
