Home / Chemical Engineering / Fluid Mechanics :: Section-17

Chemical Engineering :: Fluid Mechanics

  1. In an incompressible flow of fluid, the fluid

  2. A.

     Temperature remains constant

    B.

     Compressibility is greater than zero

    C.

     Density does not change with pressure & temperature

    D.

     Is frictionless


  3. The dimension of kinematic viscosity is

  4. A.

     ML⁻²T⁻¹

    B.

     L²T⁻¹

    C.

     ML⁻²T⁻²

    D.

     None of these


  5. Dimension of kinematic viscosity is

  6. A.

     MLT⁻¹

    B.

     L² . T⁻¹

    C.

     L²T

    D.

     L² . T⁻²


  7. The drag co-efficient for a bacterium moving in water at 1 mm/s, will be of the following order of magnitude (assume size of the bacterium to be 1 micron and kinematic viscosity of water to be 10⁻⁶m²/s).

  8. A.

     24000

    B.

     24

    C.

     0.24

    D.

     0.44


  9. The ratio of hydrodynamic boundary layer to thermal boundary layer thickness in case of liquid metals is

  10. A.

     < 1

    B.

     1

    C.

     > 1

    D.

     2


  11. The hydraulic radius for flow in a rectangular duct of cross-sectional dimension H, W is

  12. A.

     √(HW/π)

    B.

     HW/2(H + W)²

    C.

     HW/4(H + W)²

    D.

     2HW/(H + W)²


  13. For water, when the pressure increases, the viscosity

  14. A.

     Also increases

    B.

     Decreases

    C.

     Remains constant

    D.

     First decreases, and then increases


  15. Boundary layer thickness in laminar flow over a flat plate increases as(where, d = distance from the leading edge.)

  16. A.

     √d

    B.

     d1/3

    C.

     d2

    D.

     d2/3


  17. Boundary layer thickness in turbulent flow over a flat plate increases as(where, d = distance from the leading edge.)

  18. A.

     √d

    B.

     d2/3

    C.

     d4/5

    D.

     d1/3


  19. Steady flow occurs, when the

  20. A.

     Conditions change steadily with time

    B.

     Conditions are the same at the adjacent points at any instant

    C.

     Conditions do not change with time at any point

    D.

     Rate of the velocity change is constant