20g of ice are at thermal equilibrium with 200g of water in a thermally isolated vessel. a 60g block of aluminum at 250 c is dropped into the water-ice solution. lf=333 kj/kg for water, specific heat of water=4.2 kj/(kg k) specific heat of aluminum 0.9 kj/(kg. k) a)-what is the final temperature at thermal equilibrium? b)-what is the entropy change of the 20g of ice?

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?

Afluid flows with a velocity field given by v=(x/t)i.. determine the local and convective accelerations when x=3 and t=1.

The filament of an incandescent lamp has a temperature of 2000k. calculate the fraction of radiation emitted in the visible light band if the filament is approximated as blackbody