You are located downwind from two oil burning power plants in rural areas. One is located 0.3km NNE of your location and burns 1400 kg of 0.5 percent sulfur oil per hour. The second plant is located 0.5 km NNW of you and burns 1600 kg/hr of fuel oil containing 0.75 percent sulfur. Aumme that both plant stakc have an effective height of 40m. The wind is blowing from the north at 3.3 m/s. For a class B stability condition, what is the SO2 concentration at your location at ground level, in micrograms per cubic meter? The wind speed is at the standard height of 10 m

3. 14-35E A water pump is used to pump water from one large reservoir to another large reservoir that is at a higher elevation. The free surfaces of both reservoirs are exposed to atmospheric pressure. The dimensions and minor loss coefficients are provided in the figure. The pump's performance is approximated by the expression Havailable = Ho - a V², where the shutoff head, Ho = 125 ft of water column, coefficient a = 2.50 ft/(gpm)², available pump head Havailable is in units of feet of water column, and the capacity V is in units of gallons per minute (gpm). Estimate the capacity delivered by the pump. Answer: 6.34 gpm 22-2₁ = 22.0 ft (elevation difference) D 1.20 in (pipe diameter) KL. entrance KL, valve 1 KL, valve 2 = 6.8 (valve 2) KL. elbow = 0.34 (each elbow-there are 3) = 0.50 (pipe entrance) 2.0 (valve 1) KL, exit = = 1.05 (pipe exit) L = 124 ft (total pipe length) e = 0.0011 in (pipe roughness) P v₁ Reservoir V₁0 22-71 55 Valve 1 Pump V/₂20 Reservoir Valve 2

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3 An electrical current of 700 A flows through a stainless steel cable having a diameter of 5 mm and an electrical resistance of 6 x 104 /m (i.e., per meter of cable length). The cable is in an environment having a tem- perature of 30°C, and the total coefficient associated with convection and radiation between the cable and the environment is approximately 25 W/m².K. (a) If the cable is bare, what is its surface temperature? (b) If a very thin coating of electrical insulation is applied to the cable, with a contact resistance of 0.02 m² K/W, what are the insulation and cable surface temperatures? (c) There is some concern about the ability of the insula- tion to withstand elevated temperatures. What thick- ness of this insulation (k = 0.5 W/m .K) will yield the lowest value of the maximum insulation temper- ature? What is the value of the maximum tempera- ture when this thickness is used? Note: The 25 W/m²K includes not only convection but also radiation.