A 172 km, 550 kV, three-phase transmission line has an inductance of 1.162 H/m and capacitance of 9.7 pF/m. It is energized at the peak of voltage cycle through a 300 Ω risistor from a bus which can be considered ”stiff”. The remote end of the line in an open circuit. One cycle after energization the pre-insertion resistor is switched out. Determine: 1. The highest voltage at the remote and of the line as a consequensce of the firt closing operation. 2. The current flowing in the resistor 1.2 ms after the first closing operation. 3. The magnitude of the voltage wave that travels down the line following the second switcghing operation

Steel is coated with a thin layer of ceramic to protect against corrosion. what do you expect to happen to the coating when the temperature of the steel is increased significantly? explain.

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?

Asingle-geared blanking press has a stroke of 200 mm and a rated capacity of 320 kn. a cam driven ram is assumed to be capable of delivering the full press load at constant force during the last 15 percent of a constant-velocity stroke. the camshaft has an average speed of 90 rev/min and is geared to the flywheel shaft at a 6: 1 ratio. the total work done is to include an allowance of 16 percent for friction a) estimate the maximum energy fluctuation b) find the rim weight for an effective diameter of 1.2 m and a coefficient of speed fluctuation of 0.10