Aset of blocks contains blocks of heights 1,2, and 4 centimeters. imagine constructing towers of piling blocks of different heights directly on top of one another. (a tower of height 6 cm could be obtained using six 1-cm blocks, three 2-cm blocks, one 2-cm block with one 4-cm block on etc) let t be the number of ways to construct a tower of height n cm using blocks from the st ( assume an unlimited supply of blocks of each size) find a recurrence relation for t1,t2,

A2-m rigid tank initially contains saturated water vapor at 100 kpa. the tank is connected to a supply line through a valve. steam is flowing in the supply line at 600 kpa and 300 c. the valve is opened, and steam is allowed to enter the tank until the pressure in the tank reaches the line pressure, at which point the valve is closed. a thermometer placed in the tank indicates that the temperature at the final state is 200°c. determine (a) the mass of steam that has entered the tank (b) the amount of heat transfer.

Air (c-1.006 kj/kg.k, r-0.287 kj/kg.k) enters a nozzle steadily at 280 kpa and 77°c with a velocity of 50 m/s and exits at 85 kpa and 320 m/s. the heat losses from the nozzle to the surrounding medium at 20°c are estimated to be 3.2 kj/kg. determine (a) the exit temperature and (b) the total entropy change for this process. solve this problem using constant specific heats.

Two slings are used to lift a girder of length l and uniform weight per unit length. what is the best position for the slings if the bending moment due to the weight of the girder is to be kept to a minimum?