With the aid of a sketch plot of shear stress versus normal stress, show how the effective angle of internal of a powder is determined from a family of yield loci. How would you expect the mass flow...

With the aid of a sketch plot of shear stress versus normal stress, show how the effective angle of internal of a powder is determined from a family of yield loci.

How would you expect the mass flow rate of particulate solids from a hole in the base of a flat-bottomed container to vary with (a) the hole diameter and (b) the depth of solids?