Consider the steady, incompressible, two-dimensional flow field of prob. 4-69. using the results of prob. 4~69(a). do thefollowing: (a) from the fundamental definition of shear strain rate (half of the rate of decrease of the angle between two initiallyperpendicular lines that intersect at a point), calculate shear strain rate exyin the xy—plane.(hint° use the lower edge andthe left edge of the fluid particle, which intersect at 90‘ at the lower-left corner of the particle at the initial ) compare your results with those obtained from the equation for exyin cartesian coordinates, i. e.,l flu + (ws . = - - —"’ 2 83‘ 6x