Definition: Fluid
A substance exists in three primary phases: Solid liquid Gas
A substance in the liquid or gas phase is referred to as a Fluid.
Difference between Solid and Fluid
Solid Fluid
Amount of molecules per unit volume are more || Amount of molecules per unit volume are less
Molecular force of attraction is more || Molecular force of attraction is less
Solids have a definite shape || Fluids have no shape
Tensile and compressive: resist || Cannot resist tensile but resist compressive
Solids can sustain a shear force; i.e.
they remain static || Fluids cannot sustain a shear force, i.e. a fluid is always in motion
Stress is a function of the rate of strain. || Stress is a function of strain.
