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

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

## Hydraulics & Fluid Mechanics According to Bernoulli’s equation for steady ideal fluid flow

total energy is constant throughout
the energy is constant along a stream-line but may vary across streamlines
velocity and pressure are inversely proportional
principle of conservation of mass holds

1/2 R
1/3 R
3/4 R
2/3 R

## Hydraulics & Fluid Mechanics The horizontal component of force on a curved surface is equal to the

force on a vertical projection of the curved surface
weight of liquid vertically above the curved surface
force on the horizontal projection of the curved surface
product of pressure intensity at its centroid and area

## Hydraulics & Fluid Mechanics Mercury is often used in barometer because

its vapour pressure is so low that it may be neglected
it is the best liquid
both (B) and (C)
the height of barometer will be less

4.2 M
4.8 M
4.6 M
4.0 M