A hollow circular nylon pipe supports a load pa=7800N which is uniformly around a cap plate at the top of the lower pipe. a second load PB is applied at the bottom. Neglect the self-weight of the pipes. Find the PB so that the tensile stress in upper part is 14.5 MPa .what is the resulting stress in the lower part?

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]