are viscous

possess surface tension

are compressible

possess all the above properties

resistance to shear stress is small

fluid pressure is zero

linear deformation is small

only normal stresses can exist

incompressible

inviscous

viscous and incompressible

inviscous and incompressible.

Newton′s law of motion

Newton′s law of viscosity

Pascal′ law

Continuity equation

fluid

water

gas

ideal fluid.