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a link to consideration about the perpetual motion machine diagram [enter image description here]

diagrams and working out are included above. the assumptions are set to minimise engineering challenge and face perpetual motion machine on a conceptual level. What is wrong about the working?

Qmechanic
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Jesse Lee
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    "No friction" seems fairly devastating. – zh1 May 30 '20 at 14:01
  • Related: https://physics.stackexchange.com/q/556/2451 and links therein. – Qmechanic May 30 '20 at 14:07
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    Perpetual motion machines don't exist, and even if they did, they don't generate any net energy. Machines that do generate net energy violate the 1st law of thermodynamics, so they don't exist either. – David White May 30 '20 at 15:41
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    I’m voting to close this question because this is just another question in the list of "Yay! I achieved perpetual motion" questions. Relevant xkcd. –  May 30 '20 at 16:52

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In the most general sense possible: if you want to demonstrate perpetual motion (i.e., "free energy") what you must do first to check your work is write down an energy balance for the device. You do this by drawing a dashed line around the device on paper, thereby establishing a control volume around it, and then do the book-keeping sums for all forms of energy that either enter, get stored inside, or exit the control volume.

Any device in which the energy leaving the control volume exceeds that entering it plus what is being stored inside it indicates an error in your analysis. Your homework assignment is then locating that error.

niels nielsen
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