A heat engine uses a tank of ice water as a cold reservoir. The engine takes in 8 kJ of heat from the hot reservoir, and the heat expelled melts 18g of ice in the tank. How much work does this engine do?

A Carnot engine operates between temperatures of 5℃ and 500℃. The output is used to run a Carnot refrigerator operating between -5℃ and 25℃. How many joules of heat energy does the refrigerator exhaust into the room for each joule of heat energy used by the heat engine?

FIGURE P21.46 shows a Carnot heat engine driving a Carnot refrigerator.a. Determine Q₂, Q₃ and Q₄.

A typical coal-fired power plant burns 300 metric tons of coal every hour to generate 750 MW of electricity. 1 metric ton = 1000 kg. The density of coal is 1500 kg/m³ and its heat of combustion is 28 MJ/kg. Assume that all heat is transferred from the fuel to the boiler and that all the work done in spinning the turbine is transformed into electric energy.a. Suppose the coal is piled up in a 10 m ✕ 10 m room. How tall must the pile be to operate the plant for one day?

A heat engine exhausts $250\mathrm{J}$ per cycle while doing $200\mathrm{J}$ of work. What is the efficiency of this engine?

In each cycle, a heat engine absorbs $1200\mathrm{J}$ from a 400°C hot reservoir, emits $700\mathrm{J}$ to 80°C cold reservoir, while doing $500\mathrm{J}$ of work. Is it physically possible for this engine to exist?

In each cycle, a heat engine absorbs $1200\mathrm{J}$ from a 400°C hot reservoir, emits $600\mathrm{J}$ to 80°C cold reservoir, while doing $600\mathrm{J}$ of work. Is it physically possible for this engine to exist?