Select the incorrect statement. metal impregnation of a carbon-graphite seal face will: select one: 1. increase wear resistance of the seal face 2. reduce the running temperature of the seal 3. increase the strength of the seal face 4. increase resistance to higher hydrostatic pressure 5. make it difficult to troubleshoot a failed seal

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?

During a steady flow process, the change of energy with respect to time is zero. a)- true b)- false

Draw the engineering stress-strain curve for (a) bcc; (b) fcc metals and mark important points.