A 5cm diameter copper sphere (of density = 8954 kg/m3, specific heat capacity = 0.3831 kJ/kg K) is initially at a uniform temperature of 10oC. The sphere is placed inside an environment having a temperature of 200oC. The surface heat transfer coefficient is h = 10 W/(m2K). Under these conditions, we can assume uniform internal temperature for the sphere. What is the temperature inside the sphere after 10 minutes in this environment?

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]