A manned spacecraft capsule has a shape of a cylinder 2.5 m in diameter and 9 m long. The air inside the capsule is maintained at 20°C, and the convection heat transfer coefficient on the interior surface is 17 W/m^2K. Between the outer skin and the inner surface is a 15-cm layer of glass-wool insulation having a thermal conductivity of 0.017 W/m. K. If the emissivity of the skin is 0.05 and there is no aerodynamic heating or irradiation from astronomical bodies. Calculate the total heat transfer rate into space at 0 K.

Apressure vessel with an r/t 20 cannot be treated as thin walled vessel. a)-trune b)- false

Asteel wire of 2 mm diameter is fixed between two points located 2 m apart. the tensile force in the wire is 250n, if its density of steel is given by 7830 kg/m3 the fundamental frequency of vibration hz? ?

Ashielded metal arc-welding operation is accomplished in a work cell by a fitter and a welder. the fitter takes 5.5 min to load components into the welding fixture at the beginning of the work cycle, and 1.5 min to unload the completed weldment at the end of the cycle. the total ength of the weld seams 1200 mm, and the travel speed used by the welder averages 300 mm/min. every 600 mm of seam length, the welding stick must be changed, which takes 0.8 min. while the fitter is working, the welder is idle (resting): and while the welder is working the fitter is idle. (a) determine the average arc-on time as a fraction of the work cycle time. (b) how much improvement in arc-on time would result if the welder used flux-cored arc welding (manually operated), given that the spool of weld wire must be changed every 10 weldments, and it takes the welder 5.0 min to accomplish the change? (c) what are the production rates for these two cases (weldments completed per hour)? attach your work and solutions.