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प्रश्न
In which direction does the force need to applied, when a single pulley is used with a mechanical advantage greater than one? How can you change the direction of force applied without altering its mechanical advantage? Draw a labelled diagram of the system.
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उत्तर
A single movable pulley can be used to obtain an M.A. greater than 1, but this is impractical as it requires exerting force in an upward direction. Instead, a fixed pulley is used in conjunction with the movable pulley to apply force in a downward direction.
The only purpose of a fixed single pulley is to shift the force's application direction in a direction that is convenient.

M.A. = `(2T)/T = 2`
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संबंधित प्रश्न
A boy uses a single fixed pulley to lift a load of 50 kgf to some height. Another boy uses a single movable pulley to lift the same load to the same height. Compare the effort applied by them. Give a reason to support your answer.
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(iv) If the free end of the string moves through distance x, find the distance by which the load is raised.
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| S. No | Types of Simple Machine | Example |
| 1. | Pulley | |
| 2. | Wheel and axle | |
| 3. | Wedge | |
| 4. | Inclined plan | |
| 5. | Lever | |
| 6. | Screw |
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