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Analysis about the First and Second Law of Thermodynamics

  1. Dec 17, 2006 #1
    Hi guys! Can anyone please help me with these questions about the 1st and 2nd Law of Thermodynamics?

    First Law of Thermodynamics

    1. An inventor has designed an electric car in the following manner. Batteries in the car power an electric motor that drives the vehicle. When the car coasts downhill or comes to a stop and its motor is not needed, the kinetic energy of the car is converted to rotational energy and is used to turn an electric generator. The generator provides electricity to charge the batteries. According to the inventor, a great deal of energy is saved in this manner, and the car can travel much longer on a single battery charger than a conventional electric car can. Will this machine work? Why or why not?

    Second Law of Thermodynamics

    1. A refrigerator causes a separation of hot and cold; cold air is maintained inside the unit while the kitchen remains warm. Is this separation a violation of the second law?

    2. An engineer designed and built the roller coaster. He was fired. Why?
  2. jcsd
  3. Dec 18, 2006 #2


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    Staff Emeritus
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    Please post some attempts at the problems, before we can help you.
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