Fluid Mechanics and Fluid Machines Set 2

the adhesion force between molecules of fluid and tube is less than the cohesion between liquid molecules ✘ the adhesion force between molecules of fluid and tube is more than the cohesion between liquid molecules ✘ the adhesion force between molecules of fluid and tube is equal to the cohesion between liquid molecules ✘ cannot say ✔

A fluid which has no viscosity ✘ A fluid which is incompressible ✘ A fluid which has no surface tension ✘ All of the above ✔

the shear stress applied to the fluid is directly proportional to the velocity gradient (du/dy) ✘ the shear stress applied to the fluid is inversely proportional to the velocity gradient (du/dy) ✘ the shear stress applied to the fluid is directly proportional to the specific weight of the fluid ✘ the shear stress applied to the fluid is inversely proportional to the specific weight of the fluid ✔

laminar sub layer ✘ turbulent sub layer ✘ solid sub layer ✘ solid layer ✔

more ✘ less ✘ not affected by change in viscosity ✘ unpredictable ✔

Increase in free stream velocity increases the boundary layer thickness ✘ Increase in free stream velocity decreases the boundary layer thickness ✘ The boundary layer thickness does not get affected by any change in free stream velocity ✘ unpredictable ✔

small ✘ large ✘ sometimes small and sometimes large ✘ cannot say ✔

small ✘ large ✘ sometimes small and sometimes large ✘ cannot say ✔

Density ✘ Stress ✘ Strain ✘ Strain Rate ✔

  [M L T – 2 ]

✘

  [M L T – 1 ]

✘

 [M L 2 T – 2 ]

✘

  [M L 2 T 2 ]

✔