Chapter 5, Problem 5.6E

For a refrigerator or air conditioner, the coefficient of performance K (often denoted as COP) is the ratio of cooling output Qc to the required electrical energy input W, both in joules. The coefficient of performance is also expressed as a ratio of powers, |Qc\/t K |W\/t where |Qc|/t is the cooling power and W/t is the electrical power input to the device, both in watts. The energy efficiency ratio (EER) is the same quantity expressed in units of Btu for Qc and W h for W|. Part A Derive a general relationship that expresses EER in terms of K. Express your answer in terms of K. EER = Submit Request Answer

Drag and Drop the correct answers in the blanks. A mass mis hanging from the end of a vertical spring that has a spring constant k. The equilibrium position of the mass, yo, is The total potential energy of the mass when it is displaced by s from the equilibrium position is given by Y. is zero + U(s) = ks + positive * negative 1 1 ks+ 21 + U(s) ks² + mgyo %3D U(s) mgyo

A system consisting of a power cycle and a heat pump cycle, each operating between hot and cold reservoirs whose temperature are 500 K and 300 K, respectively. All energy transfers are positive in the directions of the arrows. The accompanying table provides two sets of steady-state data, in kW. For each set of data, determine if the system is operating in accord with the first and second laws of thermodynamics. Power cycle QHQc W cycle (a) 60 40 20 (b) 120 80 40 Heat pump cycle QHQ'cW'cycle 60 20 80 20 80 100 Power cycle- Hot reservoir, TH= 500 K O'H J Qc o'c Cold reservoir, Te= 300 K W cycle Heat pump

Describe two ways in which artificial intelligence paving the way for driverless cars / autonomous cars that can improve energy conservation and help us face the adverse effects of climate change.

In a police investigation of tyre marks, it was concluded that a car while in motion along a straight level road had skidded for a total disțance of 50m. after the brakes were applied. If the coefficient of friction between the tyres and the pavement is estimated as 0.50 and g = 9.8 m/s?, the probable speed of the car, just before the brakes were applied would be f 45 km/h 3) 62.5 km/h 2 2) 79.70 km/h 4) .98 km/h

mechanical principles  Examine devices which function to store mechanical energy in their operation.

you are with your father with his motorbike on the way to your school. In the middle of your travel, the gas was empty. Luckily there is a gas station nearby. Your father asked you to buy 2 liters of 100 worth of money per 2 liters "premium" gasoline advertised with r=13. But you choose to buy a 93 worth of money per 2 Liters ordinary fuel with r=8. (a) how much decrease in the ideal efficiency results from this decrease in the compression ratio? Use y=1.40. (b) Is it greater than the difference in price?

A cryogenic substance is found to have a specific heat capacity (at constant volume) c_v that varies with temperature according to c_v = AT^2, where A is an empirically derived constant with units J/(K^3 kg). If 220 J of energy must be transferred thermally (at constant volume) to an 8,750 mg sample of this substance to raise the temperature of the sample from 1.0 K to 6.6 K, what is the value of A? Your Answer: Answer units

Construct a qualitative work-energy bar chart for a process that is consistent with the equation below. Then describe in words and with a sketch a process that is consistent with both the equation and the bar chart. (1/2) (400 N/m) (0.20 m)² = (1/2) (0.50 kg) v² + (0.50 kg) (9.8 m/s²) (0.80 m)