The post is made of Douglas fir and has a diameter of 100 mm. It is subjected to the load of 20 kN and the soil provides a frictional resistance distributed along its length and varies linearly from w=3.4 kN/m at y=0 m to w=18 kN/m at y=2 m. Neglect the weight of the post. Determine the force F at its bottom needed for equilibrium and what is the displacement of the top of the post A with respect to its bottom B?

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.