//to find resistance added to ckt clc; Rrot=.061; R2=Rrot/2; f=50; P=12; w_s=(120*f/P)*(2*%pi/60); s=0.045; w=(1-s)*w_s; P=200*10^3; T_fan=P/w; I2=sqrt(T_fan*w_s*s/(3*R2)); E2=I2*R2/s; n=450; ww=2*%pi*n/60; nn=500; ss=(nn-n)/nn; Tnew=T_fan*(ww/w)^2; Rt=(3/w_s)*(E2*ss)^2/(ss*Tnew); Rext=Rt-R2;disp(Rext,'external resistance(ohm)');