0.05 m^3 of spherical silver particles (particle radius =5x10^-7m) are heated until they melt completely. Careful measurements show that 45,892,600 Joules of heat are absorbed by the particles during melting. Given the material data below, please calculate the surface energy per unit area (gsv) of silver in units of J/m^2. ΔHm(silver) = 88,000 J/kg, p(silver) = 10,490 kg/m^3. Note: ΔHm and p have been provided in units to make the calculation as straightforward as possible. There should be no need to convert these units to g, cm^3, etc. Recall that ΔHm is the latent heat.

Fluids at rest possess no flow energy. a)- true b)- false

Refrigerant 134a enters an insulated compressor operating at steady state as saturated vapor at -26°c with a volumetric flow rate of 0.18 m3/s. refrigerant exits at 9 bar, 70°c. changes in kinetic and potential energy from inlet to exit can be ignored. determine the volumetric flow rate at the exit, in m3/s, and the compressor power, in kw.

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.