Aheat pump cycle is used to maintain the interior of a building at 20°c. at steady state, the heat pump receives energy by heat transfer from well water at 9°c and discharges energy by heat transfer to the building at a rate of 120,000 kj/h. over a period of 14 days, an electric meter records that 1000 kw • h of electricity is provided to the heat pump. determine: (a) the amount of energy that the heat pump receives over the 14-day period from the well water by heat transfer, in kj. (b) the heat pump coefficient of performance. (c) the coefficient of performance of a reversible heat pump cycle operating between hot and cold reservoirs at 15°c and 9°c.

An object is located 30.0 cm from a concave mirror. the focal length is 15.0 c,. what is the image distance? a. 30.0 cm b. -10 cm c. 10.0 cm d. -30.0 cm

As part of an industrial process, air as an ideal gas at 10 bar, 400k expands at steady state through a valve to a pressure of 4 bar. the mass flow rate of air is 0.5 kg/s. the air then passes through a heat exchanger where it is cooled to a temperature of 295k with negligible change in pressure. the valve can be modeled as a throttling process, and kinetic and potential energy effects can be neglected. (a) for a control volume enclosing the valve and heat exchanger and enough of the local surroundings that the heat transfer occurs at the ambient temperature of 295 k, determine the rate of entropy production, in kw/k. (b) if the expansion valve were replaced by an adiabatic turbine operating isentropically, what would be the entropy production? compare the results of parts (a) and (b) and discuss.

A1,700kg car is being used to give a 1,400kg car a push start by exerting a force of 140n the impulse on the smaller car during the 30.0s of contact is +670kg*m/s. what is the impulse of the smaller car on the larger car? -814 kg*m/s 0kg *m/s -670kg*m/s -550kg*m/s