Determine the rrns value of a semi-circular current wave which has a maximum value of a.

The equation of a semi - circular wave isx2+y2=a2  (or)   y2=x2-a2Irms=12a∫-a+ay2dxIrms2=12a∫-a+a(a2-x2)dx=12a∫-a+a(a2-x2)dx=12a|a2x-x33|-a+a=12a(a3-a33+a3-a33)=2a33Irms=2a23=23a