Two unequal circles have diameter with radius 35mm and 20mm and the center distance is 90mm. Draw a common internal tangent to this two circles

Explain the difference laminar and turbulent flow. explain it with the shear stress and the velocity profiles.

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]

For each of the following process: a) sketch the p-v diagram, b)sketch t-s diagram, c) sketch t-v diagram, d) sketch the boundary work on one of the diagrams (a, b or c) and e) sketch the reversible heat transfer on one of the diagrams (a, b or c): 1- isobaric process from compressed liquid to superheated vapor 2- isothermal process from compressed liquid to superheated vapor 3- isentropic process from compressed liquid to superheated vapor