An inductor of =6.95 H with negligible resistance is placed in series with a ℰ=12.5 V battery, a =3.00 Ω resistor, and a switch. The switch is closed at time =0 seconds. A square loop circuit containing a battery with E M F script E, an open switch S, and inductor of inductance L, and a resistor of resistance R, all connected in series. Calculate the initial current at =0 seconds. (=0 s)= 0 A Calculate the current as time approaches infinity. max= ___ A Calculate the current at a time of 1.85 s. (=1.85 s)= ___A Determine how long it takes for the current to reach half of its maximum. = ___s

Amass of 1.5 kg of air at 120 kpa and 24°c is contained in a gas-tight, frictionless piston-cylinder device. the air is now compressed to a final pressure of 720 kpa. during the process, heat is transferred from the air such that the temperature inside the cylinder remains constant. calculate the boundary work input during this process.

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?

Avolume of 2.65 m3 of air in a rigid, insulated container fitted with a paddle wheel is initially at 264 k, 5.6 bar. the air receives 432 kj by work from the paddle wheel. assuming the ideal gas model with cv = 0.71 kj/kg • k, determine for the air the amount of entropy produced, in kj/k