Ah Beng and his wile Just bought a ready studio house In the MesaHl spartment. His...

 

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Ah Beng and his wile Just bought a ready studio house In the MesaHl spartment. His wie lovee to prepare dishes and wiehes to have a complete set of ididhen applianoes. However, Ah Beng works as a construction worker with limilted Income. Owing to COVID-19 pandemic, his salary eventuelly being cut by his company. To satisly his wife's expectation, he wert to a nearby second-hand electrical store and purchased some kltchen appliances, As electrical upplianoes aged, the efficlency (7) of the electrioal appliunces will be < 100% with old wires, electrical droults, resistors, and other bullt-in electrical components. x 100% nWetactual) : Efciency (%) Wecdeoty: Ideal required electrical power (W) Walactua: Actual required electrical power (W) For all his electrical appliances, the specifications are summarized in the table below: appliances, the specifications are summarized in the table below: No. Appliance Efficiency, n (%) Voltage, V (V) Current, I (A) Resistance, R (2) Microwave oven 75 N/A 5.4 22.22 Air fryer 88 220 N/A 32.84 Rice cooker 95 240 3.3 N/A Pressure cooker 94 220 7.5 N/A Blender 89 N/A 5.8 20.69 Refrigerator 83 200 N/A 30.30 Steam cooker 77.7 200 4.4 N/A 8. Bread maker 92 230 8.3 N/A * N/A: Not available. (a) Calculate the ideal required electrical powers of all the electrical appliances. [8 marks] [4 marks] (b) Calculate the actual required electrical powers of all the appliances. (c) If the kitchen could be modelled as a closed and adiabatic system, calculate the rate of [4 marks] energy change of the kitchen if all the appliances are in used concurrently. (d) If the kitchen can be modelled as a closed but non-adiabatic system, calculate the heat a rate of energy change of 5750 W when only microwave oven, air fryer, rice cooker, and [4 marks] transfer rate and determine its direction (in or out of the kitchen) if the kitchen is experiencing refrigerator are in used. 234 567 Ah Beng and his wile Just bought a ready studio house In the MesaHl spartment. His wie lovee to prepare dishes and wiehes to have a complete set of ididhen applianoes. However, Ah Beng works as a construction worker with limilted Income. Owing to COVID-19 pandemic, his salary eventuelly being cut by his company. To satisly his wife's expectation, he wert to a nearby second-hand electrical store and purchased some kltchen appliances, As electrical upplianoes aged, the efficlency (7) of the electrioal appliunces will be < 100% with old wires, electrical droults, resistors, and other bullt-in electrical components. x 100% nWetactual) : Efciency (%) Wecdeoty: Ideal required electrical power (W) Walactua: Actual required electrical power (W) For all his electrical appliances, the specifications are summarized in the table below: appliances, the specifications are summarized in the table below: No. Appliance Efficiency, n (%) Voltage, V (V) Current, I (A) Resistance, R (2) Microwave oven 75 N/A 5.4 22.22 Air fryer 88 220 N/A 32.84 Rice cooker 95 240 3.3 N/A Pressure cooker 94 220 7.5 N/A Blender 89 N/A 5.8 20.69 Refrigerator 83 200 N/A 30.30 Steam cooker 77.7 200 4.4 N/A 8. Bread maker 92 230 8.3 N/A * N/A: Not available. (a) Calculate the ideal required electrical powers of all the electrical appliances. [8 marks] [4 marks] (b) Calculate the actual required electrical powers of all the appliances. (c) If the kitchen could be modelled as a closed and adiabatic system, calculate the rate of [4 marks] energy change of the kitchen if all the appliances are in used concurrently. (d) If the kitchen can be modelled as a closed but non-adiabatic system, calculate the heat a rate of energy change of 5750 W when only microwave oven, air fryer, rice cooker, and [4 marks] transfer rate and determine its direction (in or out of the kitchen) if the kitchen is experiencing refrigerator are in used. 234 567