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Question
State three differences between the three classes of levers.
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Solution
| Class I | Class II | Class III | |
| 1. | It has the fulcrum between the load and effort. | It has the load between the fulcrum and effort. | It has an effort between the fulcrum and the load. |
| 2. | The effort arm can be shorter, equal to or longer than the load arm. | The effort arm is bigger than the load arm. | The effort arm is always shorter than the load arm. |
| 3. | The mechanical advantage can be less than, equal to, or greater than 1. | The mechanical advantages are always greater than 1. | The mechanical advantages are always less than 1. |
| 4. | The load and effort are in the same direction. | The load and effort are in opposite directions. | The load and effort are in opposite directions. |
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Name the load, effort, and fulcrum.
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