It is desired to produce an aligned carbon fiber–epoxy matrix composite having a longitudinal tensile strength of 500 MPa. Calculate the volume fraction of fibers necessary if (1) the average fiber diameter and length are 0.01 mm and 0.5 mm, respectively; (2) the fiber fracture strength is 4.0 GPa; (3) the fiber–matrix bond strength is 25 MPa; and (4) the matrix stress at composite failure is 7.0 MPa.

The force on a cutting tool are 2600n vertically downward and 2100 horizontal. determine the resultant force acting on the tool and the angle at which it acts.

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?

Journeyman training is usually related (clo2) a)-to specific tasks b)-to cost analysis of maintenance task c)-to control process to ensure quality d)-to installation of machinery