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| The Inclined Plane |
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| A heavy load may be raised more easily by pulling it up along a sloping surface than by lifting it vertically. For example, heavy barrels are often loaded into vans by passing two ropes round them and hauling them up an incline formed by two stout planks held apart by iron rods. As seen in figure below, the use of ropes in this |
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| manner also brings in the principle of moving pulley; the barrel in this case acts as its own pulley. It is believed that this method was used by Egyptians in building their famous Pyramids. |
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| Figure above shows a load being pulled up an inclined plane AB, friction being reduced by having the load on a trolley. |
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| In order to raise the load through a vertical height 'h', the effort has to be exerted through a longer distance equal to the length of the plane 'l'. |
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| It is important to realise that the distance through which the load is overcome is 'h' and not 'l', because the weight of the load always acts vertically downwards. |
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| It follows that the velocity ratio is given by the following expression: |
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| The mechanical advantage may be obtained by the Principle of work as follows: |
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| Load x Distance moved by load = Effort x Distance moved by effort |
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Force Work Power Energy and Machines
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