Fluid Mechanics and Hydraulic Machines (3141906) MCQs

MCQs of Viscous and Turbulent Flow

Showing 11 to 20 out of 22 Questions
1 2 3
11.
What is the ratio of maximum velocity to average velocity, when the fluid is passing through the pipe and flow is laminar?
(a) 1/2
(b) 2
(c) 3/2
(d) 2/3
Answer:

Option (b)

12.
The shear stress in a round pipe with laminar flow in it
(a) remains constant over the cross-section
(b) is zero at the centre and varies linearly with pipe radius
(c) is zero at the pipe wall and varies linearly to the centre
(d) varies parabolically across the cross-section
Answer:

Option (b)

13.
Which of the followings is a wrong statement in the context of laminar flow through a pipeline?
(a) shear stress is zero at the centre and varies linearly with pipe radius
(b) head loss is proportional to the square of the average flow velocity
(c) the friction factor varies inversely with flow Reynolds number
(d) no dispersion of dye injected into the flow stream
Answer:

Option (b)

14.
Pressure loss for laminar flow through the pipe is dependent
(a) directly on the square of flow velocity
(b) directly on the square of the pipe radius
(c) directly as the length of pipe
(d) inversely on the viscosity of flowing medium
Answer:

Option (c)

15.
What is the ratio of maximum velocity to average velocity, when the fluid is passing through two parallel plates and flow is laminar?
(a) 1/2
(b) 2
(c) 3/2
(d) 2/3
Answer:

Option (c)

16.
For laminar flow between two fixed parallel plates, the flow velocity
(a) is constant over the cross-section
(b) varies parabolically across the cross-section
(c) is maximum at the centres, zero at the plates and the variation in between is linear
(d) varies as three-halves power of distance from the midpoint
Answer:

Option (b)

17.
The shear stress between two parallel fixed plates with a laminar flow between them:
(a) varies directly as the distance from the midplane
(b) varies inversely as distance from the midplane
(c) varies parabolically across the gap
(d) remains constant across the gap
Answer:

Option (a)

18.
The friction factor for laminar flow in a circular pipe is 0.01. This corresponds to a flow Reynolds number equal to
(a) 400
(b) 800
(c) 1600
(d) 2000
Answer:

Option (c)

19.
During which case will the power loss be maximum?
(a) High viscosity oil
(b) Low viscosity oil
(c) High viscosity water
(d) Low viscosity water
Answer:

Option (a)

20.
The losses are more in
(a) laminar
(b) turbulent
(c) transition
(d) critical
Answer:

Option (b)

Showing 11 to 20 out of 22 Questions
1 2 3