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Two Questions

  1. Feb 14, 2006 #1
    A system is developed as shown in the diagram attached. The ball is initially given a push so that it falls onto a turbine connected to generator which produces electricity. After rotating the turbine the ball fall down a narrow tube with a valve into the water again the ball rises again and is again given a slight push and the whole process is repeated again and again. In this way energy is being "created". The question is: How does this machine obeys the principle of conservation of energy?
    Secondly, Why does a raider raiding a bike falls when the bike is stationary but does not fall when its moving? I know that this question has been asked before but I cant find it.
    Any help will be appreciated.:smile:
    (Pardon me for my bad english.)

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  2. jcsd
  3. Feb 14, 2006 #2


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    Do you think it is possible to push the ball through the valve and into the water without doing any work?
  4. Feb 14, 2006 #3
    No I dont. In my opinion the KE of the ball will be used to open the valve...
  5. Feb 14, 2006 #4


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    And, of course, the ball will have lost some of its energy in turning the turbine.
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