A ductile AISI 1030 hot-rolled steel bar is stressed. Using the distortion-energy and maximum-shear-stress theories determine the factors of safety for the following plane stress states: a) σx = 20 ksi, σy = 15 ksi
b) σx = 15 ksi, σy = −20 ksi
c) σx = 20 ksi, τxy = −15 ksi
d) σx = −10 ksi, σy = 15 ksi, τxy = −10 ksi
e) σx= −24 ksi, σy = −20 ksi, τxy = −15 ks

Apiston-cylinder with a volume of 0.25 m3 holds 1 kg of air (r 0.287 k/kgk) at a temperature of 100 c. heat transfer to the cylinder causes an isothermal expansion of the piston until the volume triples. how much heat is added to the piston-cylinder?

Machinery that is a key part of the process and without which the plant or process cannot function is classifed as: (clo4) a)-critical machinery b)-essential machinery c)-general purpose machinery d)-none of the specified options.

Athin walled concentric tube exchanger is used to cool engine oil from 160°c to 60°c with water that is available at 25°c acting as a coolant. the oil and water flow rates are each at 2 kg/s, and the diameter of the inner tube is 0.5 m and the corresponding value of the overall heat transfer coefficient is 250 w/m2. oc. how long must the heat exchanger be to accomplish the desired cooling? cpwater=4.187 kj/kg-candcpengine el=2.035 kj/kg·°c, oil . 120]