A raised weight can produce work, but in doing so it must necessarily sink from its height, and, when it has fallen as deep as it can fall, its gravity remains as before, but it can no longer do work.
-- Hermann von Helmholtz
   
Hermann von Helmholtz   Name:
Hermann von Helmholtz
Type:
Physicist
Nationality:
German
Birth:
August 31, 1821
Death:
September 8, 1894
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