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Comparing the Mechanical Advantage of Levers (PH 14A) Problem How do the mechanical advantages of first-class, second-class, and third-class levers differ? Pre-Lab Discussion (30 points) 1. Designing Experiments Why are you told in Step 1 to record the weight of the 500 g mass as the output force for every first-class and second-class lever that you will use in this investigation? 2. Calculating How will you calculate the actual mechanical advantage (AMA) of the levers in this investigation? 3. Predicting What factors do you predict will affect the actual mechanical advantage of the levers in this investigation? 4. Controlling Variables Identify the manipulated, responding, and controlled variables in this investigation. a. Manipulated variables b. Responding variable c. Controlled variable 5. Predicting Which class of levers do you expect to have the greatest actual mechanical advantage? Explain your answer. Observations (45 points) Data Table 1 Fulcrum Position Output Arm (cm) Input Arm (cm) Output Force (N) Input Force (N) Actual (cm) Mechanical Advantage First-Class Lever 50 50 50 Second-Class Lever 10 10 10 Third-Class Lever 10 10 10 Analysis and Conclusion (25 points) 1. Analyzing Data How did moving the fulcrum of the first-class lever closer to the output force affect the actual mechanical advantage? 2. Comparing and Contrasting Did changing the lengths of the input and output arms affect the actual mechanical advantage of all three classes of levers in the same way? Explain your answer. 3. Drawing Conclusions Based on the mechanical advantages that you calculated for each class of lever, how do third-class levers differ from the other two types? 4. Drawing Conclusions How could a third-lever be useful? (Think of the advantages of using a broom) 5. Drawing Conclusions What could you do to any lever to increase its mechanical advantage?