עמוד:31

Enrichment Scientific Literacy to A Look Contradict to the the Past Law – An of Example Conservation that Appeared of Energy Read the following text and answer the questions that follow . Orffyreus’s Wheel In the beginning of the 18 th century , in Germany , a man by the name of Orffyreus presented an amazing invention – a very large wheel , several meters in diameter . Orffyreus would set the wheel on a stage , push it lightly and then step back . The huge wheel would gain more and more speed , reach a certain velocity , and then maintain it without any apparent source of energy . But Orffyreus did not stop at this . He connected a rope to the wheel , which he used to pump water and to lift heavy weights . Even after doing this , the wheel continued to turn with no need to apply any external force . Orffyreus’s wheel was a machine of perpetual motion , or in Latin , perpetuum mobile * . Orffyreus did not disclose his secret . People attempted to uncover the secret and show that it was impossible , but to no avail . A committee that inspected the wheel thoroughly locked it in a room when still turning , only to return two months later and discover that it was still turning . One day , however , one of Orffyreus’s maids admitted that she caused the wheel to turn . She did this by turning a crank that was attached to the wheel under the floor . Before Orffyreus’s time , many inventors tried to invent a machine of eternal motion . Even Leonardo da Vinci , the great 15 th-16 th century Italian inventor and artist , never succeeded . None of them ever succeeded in this endeavor . Perpetuum mobile : A machine that moves incessantly , without slowing down , even when not supplied with energy after its initial starting up . During the operation of any machine , its kinetic energy turns into heat and so the machine gradually slows down until it stops ( provided it is not supplied with energy ) . If this does not occur , it means that the machine is producing energy on its own , out of nothing . This contradicts the law of conservation of energy . Such a machine is , of course , inconceivable according to the currently accepted laws of physics .

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