Calculate the response of an undamped system to the excitation of a half sine curve. Assume zero initial conditions. a) Using the arbitrary input method (� = 0 for h(�)) (hint: how do you treat � > � ?) b) Using Laplace transform method (hint: how do you use superposition in this case, �(� + �) = �(�) + �(�)?)

What precautions should you take to prevent injuries when dealing with heavy loads?

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?

How to increase the thermal officiency of an ideal simple rankino cycle? among these methods, which one is the best and why?