## Hydraulics & Fluid Mechanics The continuity equation pi V,A,= p2V2A2 is based on the following assumption regarding flow of fluid (where pi and p2 are mass densities.)

uniform flow
incompressible flow
frictionless flow

(ii) and (iv)
(i) and (iv)
(i) and (iii)
(ii) and (iii)

## Hydraulics & Fluid Mechanics At the centre line of a pipe flowing under pressure where the velocity gradient is zero, the shear stress will be

could be any value
negative value
maximum
minimum

## Hydraulics & Fluid Mechanics The normal stress is same in all directions at a point in a fluid

irrespective of the motion of one fluid layer relative to an adjacent layer
only when the fluid is frictionless
only when the fluid is incompressible and has zero viscosity
When there is no motion of one fluid layer relative to an adjacent layer

## Hydraulics & Fluid Mechanics The shear stress distribution for a fluid flowing in between the parallel plates, both at rest, is

zero at plates and increases linearly to midpoint
parabolic distribution across the section
zero at the mid plane and varies linearly with distance from mid plane
constant over the cross section

venturi
rotameter
orifice plate
pitot tube