A. 0
B. r/2
C. r
D. 2r
Related Mcqs:
- The boundary layer thickness at a distance of l m from the leading edge of a flat plate, kept at zero angle of incidence to the flow direction, is O.l cm. The velocity outside the boundary layer is 25 ml sec. The boundary layer thickness at a distance of 4 m is__________________?
A. 0.40 cm
B. 0.20 cm
C. 0.10 cm
D. 0.05 cmAssume that boundary layer is entirely laminar
- The boundary layer thickness in turbulent flow varies as______________?
A. x”7
B. x,/2
C. x4/5
D. x3/5where x is the distance from leading edge
- If x is the distance from leading edge, then the boundary layer thickness in laminar flow varies as________________?
A. x
B. x
C. x
D. x/7 - The correct relationship among displacement thickness d, momentum thickness m and energy thickness e is_________________?
A. d > m > e
B. d > e > m
C. e > m > d
D. e > d > m - When time of closure tc = L/v0 (where L is length of pipe and v0 is speed of pressure wavE., the portion of pipe length subjected to maximum head is__________________?
A. L/4
B. L/3
C. L/2
D. L - The distance from pipe boundary, at which the turbulent shear stress is one-third die wall shear stress, is_______________?
A. 1/3 R
B. 1/2 R
C. 2/3 R
D. 3/4Rwhere R is the radius of pipe
- The distance y from pipe boundary, at which the point velocity is equal to average velocity for turbulent flow, is________________?
A. 0.223 R
B. 0.423 R
C. 0.577 R
D. 0.707 Rwhere R is radius of pipe
- The length of a pipe is 1 km and its diameter is 20 cm. If the diameter of an equivalent pipe is 40 cm, then its length is_____________________?
A. 32 km
B. 20 km
C. 8 km
D. 4 km - A fluid of kinematic viscosity 0.4 cm2/sec flows through a 8 cm diameter pipe. The maximum velocity for laminar flow will be__________________?
A. less than 1 m/sec
B. 1 m/sec
C. 1.5 m/sec
D. 2 m/sec - The horse power transmitted through a pipe is maximum when the ratio of loss of head due to friction and total head supplied is________________?
A. 1/3
B. 1/4
C. 1/2
D. 2/3
