A glass (k = 1.1 W/m. K) spherical tank is filled with chemicals undergoing exothermic reaction. The reaction keeps the inner surface temperature of the tank at 80°C. The tank has an inner radius of 0.5 m and its wall thickness is 10 mm. Situated in surroundings with an ambient temperature of 15°C and a convection heat transfer coefficient of 70 W/m2 .K, the tank’s outer surface is being cooled by air flowing across it at 5 m/s. In order to prevent thermal burn on individuals working around the container, it is necessary to keep the tank’s outer surface temperature below 50°C. Determine whether or not the tank’s outer surface temperature is safe from thermal burn hazards.

Amass of m 1.5 kg of steam is contained in a closed rigid container. initially the pressure and temperature of the steam are: p 1.5 mpa and t 240°c (superheated state), respectively. then the temperature drops to t2= 100°c as the result of heat transfer to the surroundings. determine: a) quality of the steam at the end of the process, b) heat transfer with the surroundings. for: p1.5 mpa and t 240°c: enthalpy of superheated vapour is 2900 kj/kg, specific volume of superheated vapour is 0. 1483 m/kg, while for t 100°c: enthalpy of saturated liquid water is 419kj/kg, specific volume of saturated liquid water is 0.001043m/kg, enthalpy of saturated vapour is 2676 kj/kg, specific volume of saturated vapour is 1.672 m/kg and pressure is 0.1 mpa.

Abrake has a normal braking torque of 2.8 kip in and heat-dissipating cast-iron surfaces whose mass is 40 lbm. suppose a load is brought to rest in 8.0 s from an initial angular speed of 1600 rev/min using the normal braking torque; estimate the temperature rise of the heat dissipating surfaces.

Assuming compressible flow of air and that the measurements are done at flagstaff a pitot static tube that gives the difference of total and static pressure measures 0.35 m of mercury. what is the velocity of air? assume the temperature to be 300k. (submit your excel or matlab calculation sheet)