Consider an electric motor with a shaft power output of 20 kW and an efficiency of 88 percent. Determine the rate at which the motor dissipates heat to the room it is in when the motor operates at full load. In winter, this room is normally heated by a 2-kW resistance heater. Determine if it is necessary to turn the heater on when the motor runs at full load.

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A: Given data The power of the heater is P=5.00 kW The coefficient of performance of the refrigerator…

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Q: An electrical power supply of 275W is required to run a refrigerator and to keep the temperature of…

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Q: An electrical power station uses 1.48  1014 J of heat input with an efficiency of 34.7%. (a) How…

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Q: The ice maker inside a refrigerator makes ice cubes at 0.0°C from water that is at 17.2°C when it…

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Q: A 1200-W electric resistance heating element whose diameter is 0.5 cm is immersed in 40 kg of water…

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Q: Due to design changes, the efficiency of an engine increases from 0.30 to 0.50. For the same heat…

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Q: A heat pump used to warm a home must employ a cycle that produces a working fluid at temperatures…

A: Temperature of heat reservoir is, TH=45°C     =318 K Temperature of cold reservoir is, TC=-15°C…

Q: What is the maximum efficiency that a heat engine could have when operating between the normal…

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Q: A heat engine operates with sink temperature 25° with the efficiency of 30%. By how many kelvins…

A: Given: The engine operates with sink temperature 25oC when it have an efficiency of 30%. To find:…

Q: If the plant operates at 50.0% of its maximum efficiency and its power output is 1.23 × 108 W, at…

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Q: How much heat QH does a heat pump with a coefficient of performance of 2.00 deliver when supplied…

A: Given,   coefficient of performance = 2.00                                           W = 4.10 kJ…

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Q: An engineer designs a heat engine using flat-plate solar collectors. The collectors deliver heat at…

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Q: An electric heater supplies heat to a system at a rate of 100W. If the system performs work at a…

A: Given: Heat supplied to the system = 110 J/sec     [1 Watt = 1 J/sec] Work done by the system = 80…

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Q: A freezer needs an input power of 93.6 W to convert 1.80 kg of water at 25.0°C to 1.80 kg of ice at…

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Q: A refrigerator (located in a 22°C kitchen) removes heat from the cold compartment (at 3.4°C) at a…

A: Given data: Higher temperature, TH=220C=22+273 K=295 K Lower temperature, TL=3.40C=3.4+273 K=276.4 K…

Q: This problem compares the energy output and heat transfer to the environment by two different typ…

A: Given:- The normal efficiency of  η1= 32.16%  η2= 43.52% The same heat transfer into the engine in…

Q: An engine that has an efficiency of 25% takes in 200 J of heat during each cycle. If the engine…

A: heat absorbed in one cycle = 200 J Heat absorbed in 4 cycles = 200 * 4  = 800 joules Heat absorbed…

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Q: . If an incandescent light bulb requires 100 units of potential energy to deliver only about 15…

A: Given , Bulb require 100 unit of potential energy to deliver only 15 units of kinetic energy ( in…

Q: If 40 million Joules of energy is put into the hot reservoir and the engine transfers 22 million…

A: Given Data:- Energy put into the hot reservoir is QH=40 million Joules Energy transfered to the cold…

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Q: An ideal heat pump is being considered for use in heating an environment with a temperature of…

A: Coefficient of performance of heat pump is,  CP=THTH-TC Here, TH is hot and TC is cold temperatures.…

Q: AN IDEAL REFRIGERATOR REMOVES HEAT AT THE RATE OF 0.10KW FROM ITS INTERIOR (+2C) AND EXHAUSTS HEAT…

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Q: A Carnot air conditioner takes energy from the thermal energy of a room at 70 F and transfers it as…

A: The temperature are given in Fahrenheit. Convert these temperatures into Kelvin.

Q: A heat pump has a coefficient of performance of 4.6 . If the heat pump absorbs 30 J of heat from the…

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Q: A refrigerator has a coefficient of performance of 2.0. In each cycle it absorbs 3.4×104 J of heat…

A: Coefficient of performance, COP = 2Heat absorbed, Q = 3.4×104 JHeat released, Qh = ?

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A: Given Heat absorbed Q=530.44J Efficiency η=0.66

Q: Which of the following constitutes a very high efficiency for a useful, working heat engine? a) 200%…

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Q: The food compartment of a refrigerator, is maintained at 4°C by removing heat from it at a rate of…

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