A sign (including its post and base) weighs 40 pounds and is supported by an 18 in by 18 in square base. If the wind applies a force of 13.2 lbs to the sign at the geometric center of the sign surface, will the sign tip over? If so, how much evenly distributed weight (sand bags) should be added to the base of the sign to keep it from tipping when the wind blows?

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.