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Question
Give two reasons why the efficiency of a single movable pulley system is not 100%.
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Solution
The efficiency of a single movable pulley system is not 100% this is because
- The friction of the pulley bearing is not zero.
- The weight of the pulley and string is not zero.
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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 |
