When a freezer stands in a room at 24 degrees C, the motor has to extract...
When a freezer stands in a room at 24 degrees C, the motor has to extract 721 W of heat from the cabinet, at -2 degrees C, to compensate for less than perfect insulation. How much power must be supplied to the motor if its efficiency is 81% of the maximum achievable?
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When a freezer stands in a room at 24 degrees C, the motor has
to extract...
b. A freezer you got from a student sale has an inside temperature of – 10C;...
b. A freezer you got from a student sale has an inside temperature of – 10C; the temperature in your dorm room is around 20C; assume the freezer is a Carnot engine; furthermore, the insulation is not perfect, and allows for heat to enter the freezer at a rate of 0.1 W. How much power is needed (in the freezer motor) to maintain the constant inside temperature? You are putting 1 liter room-temperature water in ice-cube trays into the freezer...
1. As the hero or heroine of a TV show, you must rescue a football player who has been frozen solid by the Evil Conspiracy a) He's being held in a freezer at a temperature of 0.00°C which ha...
1. As the hero or heroine of a TV show, you must rescue a football player who has been frozen solid by the Evil Conspiracy a) He's being held in a freezer at a temperature of 0.00°C which has a coefficient of per- formance equal to 0.600 times the ideal K. The temperature of the room is 19.0°C If the freezer gains heat from the room at a rate of 48.0W, how much power does the freezer need? b) You...
1. A Carnot engine has a hot reservoir at 250 degrees C, and a a cold...
1. A Carnot engine has a hot reservoir at 250 degrees C, and a a cold reservoir at 25.0 degrees C. What is the efficiency of this engine? A) 10% B) 43% C) 57% D) 90% 2. A heat engine does 50 J of work and dumps 30 J of heat into the cold reservoir. How much heat was absorbed from the hot reservoir? A) 20 J B) 30 J C) 50 J D) 80 J 3. A heat engine...
3. An electric motor draws 2238 W and 12 A when operating on a 240 V source. Determine the (a) Po...
3. An electric motor draws 2238 W and 12 A when operating on a 240 V source. Determine the (a) Power factor of the motor. (b) Apparent power input to motor. (c) True power input to motor. (d) Horsepower output of the motor if it is 75% efficient. 4 The follwing s found on the nameplate of a motor. 3 hp 60 Hz 1 phase 120/240 V 34/17 A 1,740 RPM irthe power factor of the motor is 0.30, what...
1)1000 W of power is supplied to an electric motor, which has an efficiency of 95%. The motor's s...
1)1000 W of power is supplied to an electric motor, which has an efficiency of 95%. The motor's shaft drives a water pump, which is 70% efficient. The system is steady. Determine the rate at which the mechanical energy of the fluid increases between the inlet and outlet of the pump, and where the difference in energy went. 2)The quality of a saturated liquid-vapour mixture is 100% when the fluid is comprised entirely of Select one: a. Compressed liquid b....
We want to determine how much the room temperature increases.....
Screen Shot 2021-01-20 at 3.33.17 PM.pngScreen Shot 2021-01-20 at 3.32.53 PM.png1. We want to determine how much the room temperature increases when a kg of ice freezes.Suppose you have a freezer that needs 1 J of energy for every 3 J of heat it removes.How much thermal energy must be removed from 1 kg of water at room temperature?How much electrical energy is used to freeze the ice?What is the total energy, including waste heat, that is dumped into the...
thermodynamics Page 5 of 12 Problem 3 (SS pts): The following figure provides the schematic o using Refrigerant 134a as the working fluid to keep a ro the outdoor air at 34 "C. The refrigeran...
thermodynamics
Page 5 of 12 Problem 3 (SS pts): The following figure provides the schematic o using Refrigerant 134a as the working fluid to keep a ro the outdoor air at 34 "C. The refrigerant enters the co leaves dhe rate of O.06 m steady site compressor at 320 kPa as a satwrated vapor w a saturated liquid. Assume there is no pressure drop in the eo stray heat transfer for the compressor the valve, leaves at 1 refrigerant leaves...
1. A heat engine operates by taking in heat at a particular temperature and a. converting...
1. A heat engine operates by taking in heat at a particular temperature and a. converting it all into work b. exhausting some of it at a higher temperature c. exhausting all of it at a lower temperature d. converting some into work and exhausting the rest at a lower temperature 2. A refrigerator a. adds cold to a substance b. transfer heat from one location to another c. changes heat to cold d. removes cold from a substance 3....
Chose the correct answer(s) from the multiple choice lists below 1. Exergy of a system is a) b) always increasing e) guided by the first and second laws of thermodynamics for reversible proce...
Chose the correct answer(s) from the multiple choice lists below 1. Exergy of a system is a) b) always increasing e) guided by the first and second laws of thermodynamics for reversible processes only Un d) limited by the second law of thermodynamics for all processes. processes, it is destroyed partly or completely). e) equal to the Gibs free energy of the system. 211two electrodes, one made of u (E.-3.06 V) and another made of Cu ΟΕ.+034V placed in an...
(might be 1 or 2, MCQ questions were having images given with them, which we couldn't...
(might be 1 or 2, MCQ questions were having images given with them, which we couldn't insert, so ignore those questions if you cannot answer, sorry for inconveinience created, i tried to delete them but might be couldn't done all) 3) Single phase induction motors work because: a) The oscillating magnetic field can induce starting torque in a rotor. b) The oscillating magnetic field can induce running torque in a rotor. c) A capacitance or inductance can create the phase...
1. As the hero or heroine of a TV show, you must rescue a football player who has been frozen solid by the Evil Conspiracy a) He's being held in a freezer at a temperature of 0.00°C which has a coefficient of per- formance equal to 0.600 times the ideal K. The temperature of the room is 19.0°C If the freezer gains heat from the room at a rate of 48.0W, how much power does the freezer need? b) You...
3. An electric motor draws 2238 W and 12 A when operating on a 240 V source. Determine the (a) Power factor of the motor. (b) Apparent power input to motor. (c) True power input to motor. (d) Horsepower output of the motor if it is 75% efficient. 4 The follwing s found on the nameplate of a motor. 3 hp 60 Hz 1 phase 120/240 V 34/17 A 1,740 RPM irthe power factor of the motor is 0.30, what...
thermodynamics
Page 5 of 12 Problem 3 (SS pts): The following figure provides the schematic o using Refrigerant 134a as the working fluid to keep a ro the outdoor air at 34 "C. The refrigerant enters the co leaves dhe rate of O.06 m steady site compressor at 320 kPa as a satwrated vapor w a saturated liquid. Assume there is no pressure drop in the eo stray heat transfer for the compressor the valve, leaves at 1 refrigerant leaves...
Chose the correct answer(s) from the multiple choice lists below 1. Exergy of a system is a) b) always increasing e) guided by the first and second laws of thermodynamics for reversible processes only Un d) limited by the second law of thermodynamics for all processes. processes, it is destroyed partly or completely). e) equal to the Gibs free energy of the system. 211two electrodes, one made of u (E.-3.06 V) and another made of Cu ΟΕ.+034V placed in an...
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