A jeweler wishes to produce 20 gold rings in one investment-casting operation. The wax parts are attached to a wax central sprue with a 20-mm diameter. The rings are located in four rows, each 15 mm from the other on the sprue. The rings require a 3-mm diameter, 12-mm long runner to the sprue. Estimate the weight of gold needed to completely fill the rings, runners, and sprues. Assume a typical ring has a 25-mm outer diameter, 19-mm inner diameter, and 5-mm width. The specific gravity of gold is 19.3.

Line joining liquid phase with liquid and solid phase mixture is known as: a) liquidus b) solidus c) tie line d) none of the mentioned

What difference(s) did you notice using a pneumatic circuit over hydraulic circuit.explain why the pneumatic piston stumbles when it hits an obstacle.

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?