A Sphere of Radius 1 Cm and Mass 100 G

Multiple Choice

A sphere of radius 1 cm and mass 100 g is sinking at a steady speed of 1 mm per second down through a fluid with viscosity of 300 Pa s. Assuming that Stokes' law applies, what is the density of the viscous fluid?

A) 500 kg m-3.
B) 1000 kg m-3.
C) 1500 kg m-3.
D) 2000 kg m-3.
E) 5000 kg m-3.ANS