The radiative heat transfer rate per unit area $$\left( {W/{m^2}} \right)$$ between two plane parallel gray surfaces (emissivity $$=0.9$$) maintained at $$400K$$ and $$300K$$ is ($${{\sigma _b} = }$$ Stephen Boltzmann constant $$5.67 \times {10^{ - 8}}\,\,W/{m^2}{K^4}$$)

For a small project with five jobs, the following data is given
(i) Draw the project network in activity on arc mode
(ii) Under $$PERT$$ assumptions, determine the distribution of project duration.

The outside diameter of a hollow shaft is twice its inside diameter. The ratio of its torque carrying capacity to that of a solid shaft of the same material and the same outside diameter is

The yield strength of a steel shaft is twice its endurance limit. Which of the following torque fluctuations represent the most critical situation according to Soderberg criterion?