A rudimentary heat sink is attached on top of a square CPU-block. The surface area of the CPUis 5 cm5 cm. The heat sink is made of 10 two-centimeter-long rectangular ns of cross section2 mm5 cm. The ns of the heat sink is attached directly on top of the CPU block. Convectiveheat transfer coecient of air around the CPU block is 20W/m2.C. Conductivity of the fin material is 240 w/m-'c. Neglecting heat transfer from the fin tip, find out the effectiveness of one fin and overall effectiveness of the heat sink surface.
State all your assumptions clearly.

When at a point two solid phase changes to one solid phase on cooling then it is known as a) eutectoid point b) eutectic point c) peritectic point d) peritectoid point

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.

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?