When a certain type of coal is burned at a power plant, 22.6 ×106×106 joules per kilogram are released that is subsequently used to boil water and produce steam. The steam then does work on the turbine to produce electricity. If power is produced at a rate of 480 megawatts as 102000 kilograms of coal are burned per hour, what is the efficiency of the power plant?

To produce 96 hp of mechanical power, an automobile engine requires a supply of heat of 4.91  105 J per second from combustion of the fuel. What is the efficiency of this engine?

As a gasoline engine is running, the amount of gasoline containing 15,000J of chemical potential energy is burned in 1 s. During that second, the engine does 3,000J of work. The burning gasoline has a temperature of about 2500 K. The waste heat from the engine flows into the air at about 300 K. What is the Carnot efficiency of a heat engine operating between these two temperatures?

4. Suppose that a nuclear power plant has an efficiency of about 0.34, and generates 1000 MW of power. It is located on the banks of a major river that is 67 m wide near the plant, approximately 3 m deep, and flows at a rate of 0.5 m/s. Suppose that the plant re-routes all of this water into the plant and dumps its waste heat evenly throughout the water, then returns the warmer water to the river. How much warmer is the river downstream of the plant compared to upstream? Water's specific heat is approximately 4184 J/kg/K, and its density is 1000 kg/m³. [Answer: The water is warmer by 4.62 K. This is a lot warmer!]

A 2.0 m2 solar panel is fully illuminated by sunlight. Assume the sunlight has a power density of 0.10 J/cm2 -s. a) If the efficiency of the solar panel is 16%, how much electrical energy will it deliver in one hour? b) If this energy is stored in a battery, how long will it keep a 100 W incandescent lightbulb burning if the bulb has an efficiency of 2.6%. (Efficiency of the lightbulb is the light out - - 100 W - to the electrical power in.)

Question 6. in one cycle, a heat engine does 700J of work and releases 1450 J of heat to a lower-temperature reservoir. What is the efficiency of this engine, in percent?

An engine takes in 600 J and exhausts 450 J each second is running. What is the engine's efficiency?