For the Streamlined Flow of a Viscous Liquid,such as Water,in

Multiple Choice

For the streamlined flow of a viscous liquid,such as water,in a capillary tube,which of the following is correct?

A) The coefficient of viscosity depends on the radius of the inside of the tube raised to the fourth power.
B) The velocity of the liquid is essentially zero at the tube walls and increases toward the center of the tube.
C) There is no pressure difference along the tube provided the tube is less than 10 cm in length.
D) The volume flow rate through the tube can never be constant.
E) None of these is correct.