Aheat pump with a cop of 2.8 is used to heat an air-tight house. when running, the heat pump consumes 5 kw of power. if the temperature in the house is 7°c when the heat pump is turned on, how long will it take for the heat pump to raise the temperature of the house to 22°c? is this answer realistic or optimistic? explain. assume the entire mass within the house (air, furniture, etc.) is equivalent to 1500 kg of air.

Around steel bar, 20 mm in diameter and 400 mm long, is placed concentrically within a brass long. tube which has an outside diameter of 30 mm and thickness 4 mm. the tube is 400 mm the upper end of the vertically placed compound bar is rigidly fixed and a collar is fitted to the bottom end. the application of a load p results in the compound rod storing a total of 5 j of energy.calculate (a) the gradually applied load; (b) the suddenly applied load; (c) the impact load that falls 100 mm and induces 5 j of energy; (d) the instantaneous stresses in both materials; and (e) the instantaneous elongation of the compound rod (egt = 200 gpa and egr = 100 gpa).