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__________________?

Related Mcqs:

1. 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

2. In a two dimensional incompressible steady flow around an airfoil, the stream lines are 2 cm apart at a great distance from the airfoil, where the velocity is 30 m/sec. The velocity near the airfoil, where the stream lines are 1.5 cm apart, is_________________?

   A. 22.5 m/sec
   B. 33 m/sec
   C. 40 m/sec
   D. 90 m/sec

3. 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 R

   where R is radius of pipe

4. A valve is suddenly closed in a water main in wl.ich the velocity is 1 m/sec and velocity of pressure wave is 981 m/ sec. The inertia head at the valve will be________________?

   A. 1 m
   B. 10m
   C. 100m
   D. none of the above

5. The boundary layer thickness in turbulent flow varies as______________?

   A. x”7
   B. x,/2
   C. x4/5
   D. x3/5

   where x is the distance from leading edge

6. The maximum thickness of boundary layer in a pipe of radius r is____________________?

   A. 0
   B. r/2
   C. r
   D. 2r

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

8. The depth ‘d’ below the free surface at which the point velocity is equal to the average velocity of flow for a uniform laminar flow with a free surface, will be_________________?

   A. 0.423 D
   B. 0.577 D
   C. 0.223 D
   D. 0.707 D

   where D is the depth of flow

9. 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

10. The ratio of average velocity to maximum velocity for steady laminar flow in circular pipes is_______________?

    A. 1/2
    B. 2/3
    C. 3/2
    D. 2