An inventor claims to have built an engine that produces2.00 MW of usable work while taking in 3.00 MW of thermalenergy at 425 K, and rejecting 1.00 MW of thermal energyat 215 K. Is there anything fishy about his claim? Explain.

1. What is the best coefficient of performance possible for a hypothetical refrigerator that could make liquid nitrogen at -190 °C and has heat transfer to the environment at 38 °C? Think: What refrigerator has the most efficiency? COP ref

1.50 moles of an ideal monatomic gas are initally at a tempeture of 317 K. If the gas gains 2550 J of heat and preforms 750 J of work. what is its final temperture

An internal combustion engine has the following characteristics: (a) the combustion chamber temperature is 1900 ᵒC; (b) the temperature in the exhaust chamber is 430 ᵒC; (c) with the consumption of the equivalent of 7.0 × 10⁹ cal of fuel the engine produces 1.4 × 10¹⁰ J of work in one hour. What is the thermal efficiency of this engine? I.    77% II.    68% III.    56% IV.    48% V.    37% VI.    25%   If necessary, consider: R = 8.314 J/mol∙K1 cal = 4.19 Jkb =1,38 x 10⁻²³ m² kg s⁻² K⁻¹

#4

Use 1025ft2 and 8ft

A nuclear power reactor has pressurized water at 300C. (Higher temperatures are theoretically possible but practically not, due to limitations with materials used in the reactor.) Heat transfer from this water is a complex process. Steam, produced in the steam generator, is used to drive the turbine-generators. Eventually the steam is condensed to water at 27C and then heated again to start the cycle over. Calculate the maximum theoretical efficiency for a heat engine operating between these two temperatures.

A nuclear power plant operates at 75 % of its maximum theoretical (Carnot) efficiency between temperatures of 645 °C and 380 °C. 1. If the plant produces electric energy at the rate of 1.6 GW, how much exhaust heat is discharged per hour?

Needs Complete typed solution of both parts with 100 % accuracy.

Q2. What is the total change in entropy when 5.0 kg Of water at 15'℃ is brought into contact with a large heat reservoir at 1000C, after the water reached the temperature of the reservoir - -4186 J/kg,K 18. O