Identify the lever classification and mechanical advantage principles for the following common tools. Match each real-world application to its correct mechanical description.
- A pry bar resting over a wooden block used to lift a heavy machinery crate.Class 1 Lever: The pivot point is located between the applied force and the load, allowing for a mechanical advantage that can vary based on pivot placement.
- A heavy-duty guillotine paper cutter slicing through a thick stack of documents.Class 2 Lever: The load is located between the pivot point and the applied force, always providing a mechanical advantage greater than one.
- A pair of tweezers being squeezed in the middle to carefully place a small microchip.Class 3 Lever: The applied force is located between the pivot point and the load, always yielding a mechanical advantage less than one while multiplying distance or speed.
Answer
The pry bar is a Class 1 lever, the paper cutter is a Class 2 lever, and the tweezers are a Class 3 lever.
By analyzing the geometry of each tool, we find that the pry bar places the fulcrum between the applied force and the resistance (Class 1). The paper cutter places the resistance between the fulcrum and the applied force (Class 2). Finally, the tweezers place the applied force between the fulcrum and the resistance (Class 3).
Step-by-Step Solution
Key Concept
Lever Classification and Mechanical Advantage