Chapter 5, Problem 5.28CU

Liquid flows at steady state at a rate of 2 lb/s through a pump, which operates to raise the elevation of the liquid 100 ft from control volume inlet to exit. The liquid specific enthalpy at the inlet is 40.09 Btu/lb and at the exit is 40.94 Btu/lb. The pump requires 3 Btu/s of power to operate. If kinetic energy effects are negligible and gravitational acceleration is 32.174 ft/s2, the heat transfer rate associated with this steady state process is most closely:   A) 2.02 Btu/s from the liquid to the surroundings. B) 3.98 Btu/s from the surroundings to the liquid. C) 4.96 Btu/s from the surroundings to the liquid. D) 1.04 Btu/s from the liquid to the surroundings.

An oil pump operating at steady state delivers oil at a rate of 10 lb/s through a 1-in.-diameter exit pipe. The oil, which can be modeled as incompressible, has a density of 70 lb/ft³ and experiences a pressure rise from inlet to exit of 40 lb/in². There is no significant elevation difference between inlet and exit, and the inlet kinetic energy is negligible. Heat transfer between the pump and its surroundings is negligible, and there is no significant change in temperature as the oil passes through the pump. Determine the velocity of the oil at the exit of the pump, in ft/s, and the power required for the pump, in hp. Step 1 Determine the velocity of the oil at the exit of the pump, in ft/s. Your answer is correct. V₂ = 26.192 Hint Step 2 * Your answer is incorrect. Win ft/s Determine the power required for the pump, in hp. i7.73 hp Attempts: 1 of 4 used

An oil pump operating at steady state delivers oil at a rate of 10 lb/s through a 1-in.-diameter exit pipe. The oil, which can be modeled as incompressible, has a density of 70 lb/ft³ and experiences a pressure rise from inlet to exit of 40 lb/in². There is no significant elevation difference between inlet and exit, and the inlet kinetic energy is negligible. Heat transfer between the pump and its surroundings is negligible, and there is no significant change in temperature as the oil passes through the pump. Determine the velocity of the oil at the exit of the pump, in ft/s, and the power required for the pump, in hp. Step 1 Your answer is correct. Determine the velocity of the oil at the exit of the pump, in ft/s. V₂ = 26.192 Hint Step 2 ft/s * Your answer is incorrect. Determine the power required for the pump, in hp. i 1.49595 hp Attempts: 1 of 4 used

An oil pump operating at steady state delivers oil at a rate of 10 lb/s through a 1-in.-diameter exit pipe. The oil, which can be modeled as incompressible, has a density of 70 lb/ft3 and experiences a pressure rise from inlet to exit of 40 lb/in². There is no significant elevation difference between inlet and exit, and the inlet kinetic energy is negligible. Heat transfer between the pump and its surroundings is negligible, and there is no significant change in temperature as the oil passes through the pump. Determine the velocity of the oil at the exit of the pump, in ft/s, and the power required for the pump, in hp. Determine the power required for the pump, in hp.

5.45 WP As shown in Fig. P5.45, an air conditioner operating at steady state maintains a dwelling at 70°F on a day when the outside temperature is 90°F. If the rate of heat transfer into the dwelling through the walls and roof is 30,000 Btu/h, might a net power input to the air conditioner compressor of 3 hp be sufficient? If yes, determine the coefficient of performance. If no, determine the minimum theoretical power input, in hp.

An oil pump operating at steady state delivers oil at a rate of 13 lb/s through a 1-in.-diameter exit pipe. The oil, which can be modeled as incompressible, has a density of 85 lb/ft3 and experiences a pressure rise from inlet to exit of 40 lb/in². There is no significant elevation difference between inlet and exit, and the inlet kinetic energy is negligible. Heat transfer between the pump and its surroundings is negligible, and there is no significant change in temperature as the oil passes through the pump. Determine the velocity of the oil at the exit of the pump, in ft/s, and the power required for the pump, in hp. Step 1 Your answer is correct. Determine the velocity of the oil at the exit of the pump, in ft/s. V₂ = 28.064 Hint Step 2 * Your answer is incorrect. ft/s Determine the power required for the pump, in hp. Win = 1.60155105 eTextbook and Media hp Attempts: 1 of 4 used

An oil pump operating at steady state delivers oil at a rate of 11 lb/s through a 1-in-diameter exit pipe. The oil, which can be modeled as incompressible, has a density of 55 lb/ft3 and experiences a pressure rise from inlet to exit of 40 lb/in². There is no significant elevation difference between inlet and exit, and the inlet kinetic energy is negligible. Heat transfer between the pump and its surroundings is negligible, and there is no significant change in temperature as the oil passes through the pump. Determine the velocity of the oil at the exit of the pump, in ft/s, and the power required for the pump, in hp. Step 1 * Your answer is incorrect. Determine the velocity of the oil at the exit of the pump, in ft/s. V₂ = i 32.08 ft/s

5.12

7.25 As shown in Fig. P7.25, a 1-lb metal sphere initially at 2000°R is removed from an oven and quenched by immersing it in a closed tank containing 25 lb of water initially at 500°R. Each substance can be modeled as incompressible. An appropriate constant specific heat for the water is c 1.0 Btu/lb °R, and an appropriate value for the metal is cm = 0.1 Btu/lb oR. Heat transfer from the tank contents can be neglected. Determine the exergy destruction, in Btu. Let To = 77°F. System boundary Metal sphere: Tmi=2000°R m=0.1 Btu/lb R mm= 1 lb Water: Twj=500°R =1.0 Btu/lb R m 25 lb FIGURE P7.25