Name _______________________________________________________________ Date ______________

Penny Wars - Experiments with Levers

Materials Needed: Ruler, Pennies, Pencil (or other object to serve as a fulcrum), Tape to hold fulcrum

Design: Set up your experiment as pictured where one side of pennies will be matched against another stack on the opposite side of your fulcrum. You will be measuring the input and output arms needed to make the pennies balance; mechanical advantage can be calculated.

mechanical advantageset up

  Length of Input Arm (cm) Length of Output Arm (cm) Calculate Mechanical Advantage
1 Penny vs 4 Pennies      
2 Pennies vs 6 Pennies      
3 Pennies vs 6 Pennies      
3 Pennies vs 8 Pennies      
3 Pennies vs 10 Pennies      
For the next set, choose your own matches.
       
       
       
       
       

1. As the length of the input arm increased, the mechanical advantage [ increased/decreased/stayed the same ]
As the length of the output arm increased, the mechanical advantage [ increased / decreased / stayed the same ]

2.In your own words describe how changing the location of the fulcrum affected the amount of force necessary to balance the single penny to the stack of pennies. You can use drawing to help with your description. Use complete sentences!