// exa 4.11 Pg 117 clc;clear;close; // Given Data Sut=600;//MPa Syt=400;//MPa Se=200;//MPa Mmin=200;// N.m Mmax=500;// N.m Tmin=60;// N.m Tmax=180;// N.m n=2;// factor of safety Mm=(Mmax+Mmin)/2;// N.mm Ma=(Mmax-Mmin)/2;// N.mm Tm=(Tmax+Tmin)/2;// N.mm Ta=(Tmax-Tmin)/2;// N.mm // sigma_xm=32*Mm/%pi/d**3 sigma_xm_into_d_cube=(32*Mm*1000)/%pi; // sigma_xa=32*Ma/%pi/d**3 sigma_xa_into_d_cube=(32*Ma*1000)/%pi; //Txym=16*Tm/%pi/d**3 Txym_into_d_cube=16*Tm*1000/%pi; //Txya=16*Ta/%pi/d**3 Txya_into_d_cube=16*Ta*1000/%pi; // sigma_m=sqrt(sigma_xm**2+3*Txym**2) sigma_m_dash=sqrt(sigma_xm_into_d_cube**2+3*Txym_into_d_cube**2);// taken sigma_m_dash = sigma_m*d**(-3) for calculation // sigma_a=sqrt(sigma_xa**2+3*Txya**2) sigma_a_dash=sqrt(sigma_xa_into_d_cube**2+3*Txya_into_d_cube**2);// taken sigma_a_dash = sigma_a*d**(-3) for calculation //tan(theta) = sigma_a/sigma_m theta = atan(sigma_a_dash/sigma_m_dash);// radian //Sm/Sut+Sa/Se= 1 where Sa/Sm=0.4348 Sm= 1/(1/Sut+0.4348/Se);// MPa Sa=0.4348 * Sm;// MPa //sigma_a=Sa/n d=(Sa/n/sigma_a_dash)**(1/3)*1000;// mm printf('\n diameter of shaft, d = %.2f mm',d) // Note - Ans in the textbook is wrong.