3a concentric tube heat exchanger for cooling lubricating oil is comprised of a thin-walled inner tube of 25-mm diameter carrying water and an outer tube of 45-mm diameter carrying the oil. the exchanger operates in counterflow with an overall heat transfer coefficient of 60 w/m2 k and the tabulated average properties.

Ahot wire operates at a temperature of 200°c while the air temperature is 20°c. the hot wire element is a tungsten wire of 5 um diameter and 2 mm in length. plot using excel current, heat transfer and heat generated by the wire for air velocity varying from 1-10 m/s in steps of lm/s? matlab the sensor voltage output, resistance, or assume nu 0.989 re033pr13 take air properties at tr (200°c20°c)/2 = 110°c properties of tungsten: c 0.13 kj/kg.k 3 p 19250 kg/m k (thermal conductivity) = 174 w/m.k

Aheavily insulated piston-cylinder device contains 0.02 m3 of steam at 300 kpa and 200 °c. 1.2 mpa. d this process. team is now compressed in a reversible manner to a pressure of etermine the entropy change and the work done on the steam during this process

The proportional limit is always greater than the yield strength for a material. a)-trune b)- false