Abar of steel has the minimum properties se=276mpa, sy=413mpa, sut=551mpa. find the factor of safety guarding against a static failure, and either the factor of safety guarding against a fatigue. failure or the expected life of the part, if a steady torsional stress of 103 mpa, an alternating torsional stress of 69 mpa, and an alternating bending stress of 83 mpa are applied to the bar

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.