Pulleys and block-and-tackles are often used to hoist objects into the upper levels of barns and garages. The supports that hold these contraptions come in various forms. Let us model the illustrated orange support as a planar truss with horizontal member that is subjected to the vertical tension load . Given the following: 90 N cm cm determine forces , , and in N in members , and . Matlab input: T = 90; AB = 100; AC = 140; theta = 15; N N N

Air inially occupying a volume of 1 m2 at 100 kpa, 27 c undergoes three internally reversible processes in series. process 1-2 compression to 500 kpa during which pv constant process 2-3 adiabatic expanslon to 100 kpa process 3-1: constant-pressure expansion to 100 kpa (a) calculate the change of entropy for each of the three processes. (b) calculate the heat and work involved in each process. (c) is this cycle a power cycle or refrigeration cycle?