Скачать или смотреть Fluids - 10. Problems Based on Viscosity

This video explains the following :
1) Problems Based on Viscosity
1) Problems Based on Stokes' Law
Que: Viscosity is property of a liquid due to which it
a) Occupies minimum surface area
b) Opposes relative motion between its adjacent layers
c) Becomes spherical in shape
d) Tends to regain its deformed position
Que: A liquid is flowing in a streamlined manner through a cylindrical pipe. Along a section containing the axis of the pipe, the flow profile will be:
Que: Three identical vessels A, B and C are filled with water, mercury and kerosene respectively up to an equal height. The three vessels are provided with identical taps at the bottom of the vessels. If the three taps are opened simultaneously, then which vessel is emptied first?
(a) Vessel B
(b) All the vessels A, B and C will be emptied simultaneously
(c) Vessel A
(d) Vessel C
Que: Water is flowing on a horizontal fixed surface such that its flow velocity varies with y (vertical direction) as v = k (2y2/a2 – y3/a3). If coefficient of viscosity for water is η, what will be shear stress between layers of water at y =a
a) ηk/a
b) η/ka
c) ηa/k
d) None of these
Que: Spherical balls of radius R are falling in a viscous fluid of viscosity  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