Amaterial is characterized by = (8 gpa)0.2. this material is used as raw material to forge a cylindrical part. the initial height of the cylindrical specimen is 25 mm and the final height is 10 mm. the volume of the specimen is constant at 10,900 mm^3. calculate the average flow stress and the average pressure required for forging.

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]