A Wisconsin train carrying coal consists of 105 carloads, each carrying 100 tons of coal. Twenty five percent of the weight of Wyoming coal is water, while the rest is coal with an energy content of 3.2 x10¹0 J/ton. a. How much energy is contained in the trainload of coal? b. A coal-fired power plant can produce electricity at a rate of 978 Megawatts. Coal power plants are, at best, about 42% efficient in converting the energy in coal to electricity. How many trainloads of coal are needed daily to keep the plant running at full capacity?

A Wisconsin train carrying coal consists of 105 carloads, each carrying 100 tons of coal. Twenty five percent of the weight of Wyoming coal is water, while the rest is coal with an energy content of 3.2 x10¹0 J/ton. a. How much energy is contained in the trainload of coal? b. A coal-fired power plant can produce electricity at a rate of 978 Megawatts. Coal power plants are, at best, about 42% efficient in converting the energy in coal to electricity. How many trainloads of coal are needed daily to keep the plant running at full capacity?

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter7: Work, Energy, And Energy Resources

Section: Chapter Questions

Problem 47PE: (a) What is the efficiency of an out-of-condition professor who does 2.10105J of useful work while...

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