//example 1.9 //page 27 clc; funcprot(0); //initialisation of variable mu=0.44; N=300; t=0.00025;//thickness R1=0.15;//radius R2=0.1;//radius pi=3.14; T=pi^2*mu*N/60/t*(R1^4-R2^4); P=T*2*pi*N/60 disp(P,"power lost in (watts)"); clear