Why it is important to prepare first the materials and tools carpentry before doing the tasks?​

Avertical steel rod of length 2.0 m and diameter 25 mm is rigidly fixed at its upper end and has a flange at its lower, free, end. what will be the maximum stress produced in the rod when a load of 20 kn is applied, (a) gradually to the lower end, (b) suddenly to the lower end, (c) by a collar falling from a height of 50 mm on to the flange?

1kg of water contained in a piston-cylinder assembly undergoes two processes in series from an initial state where the pressure is 3.0 bar and the temperature is 150°c process 1-2: the water is compressed isothermally to a volume of 0.25 m^3 with 120 kj of work being done to the system. process 2-3: the water is heated at constant volume to a final pressure of 10 bar. a. find the change in internal energy for the system. b. calculate the amount of heat transferred, in kj. c. sketch both processes on a t-v diagram. (196.33 kj/kg, 76.33 kj)

An air-conditioning system consists of a heating section and an evaporative cooler. air enters the heating section at 10°c and 70 percent relative humidity at a rate of 30m^3/min, and it leaves the evaporative cooler at 20°c and 60 percent relatively humidity. if the air conditioning system operates at a total pressure of 98 kpa, determine (a) the temperature and relative humidity of the air when it leaves the heating section, (b) the rate of heat transfer in the heating section, and (c) the rate of water added to air in the evaporative cooler