Determine the torque required to rotate a 49.2-mm-diameter vertical cylinder at a constant angular velocity of 24.8 rad/s inside a fixed outer cylinder that has a diameter of 50 mm. the gap between the cylinders is filled with sae 30 oil at 15.6degc. the length of the inner cylinder is 225 mm. neglect bottom effects and assume the velocity distribution in the gap is linear.

Asteam is contained in a rigid tank with a volume of 1 m3. initially, the pressure and temperature are 7 bar and 500 oc, respectively. the temperature drops due to cooling process. determine: (1) the temperature at which condensation begins in °c, (2) the fraction of the total mass that has condensed when the pressure decreased to 0.5 bar. (3) the volume in m3 occupied by saturated liquid at the final state?