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Trial 1 - Egg seesaw

1. Have you played on a seesaw or teeter-totter?
   
   
   

   Yes

   
   
   

   No

   
   
   Draw a picture of a seesaw.
   
   
   
2. Obtain two hard-boiled eggs. Using markers or crayons, draw faces on your eggs. You may use your eggs from Investigation 1 if you have them.

   

3. Build a cradle for your eggs. You can make one from scratch or improve one of your designs from Investigation 1.

4. Build a seesaw, using a piece of wood or a meter stick. It will need a balance point. You can build this using cardboard and tape. It will balance more easily if the top is flat.

   

5. Figure out a way to have the cradles rest on the seesaw or hang from the seesaw so that they don't fall off. Here is an example, but you can do it your own way. This example shows books to lift the seesaw, but they may not be needed.

   

6. Try to make the two eggs balance each other. What did you do to make them balance?
   
   
   
   

7. Measure the distance from each egg to the balance point. When they balance, what are the two distances?

   

   
   Distance #1 (cm) =
   
   Distance #2 (cm) =
   
   
   
8. Do you think the two distances should be the same?
   Which egg do you think is heavier?
   
   

   Egg #1

   
   
   

   Egg #2

   
   
   

   Neither. Both are the same.

   
   
   
   
9. Now weigh your two eggs with their cradles. Connect the force sensor. Refer to Technical Hints to connect the force sensor. Zero the force sensor. Refer to Technical Hints to zero the force sensor.

10. Using the force sensor, weigh each egg in its cradle. Record your measurement. Refer to Technical Hints to record a single measurement.
    
    

    

    
    weight of egg #1 =
    
    weight of egg #2 =
    
    
    
11. Which egg in its cradle is heavier?
    
    
    

    egg #1

    
    
    

    egg #2

    
    
    

    Neither (both are the same)

    
    
    
    
12. Does this agree with your prediction in Question 8?
    
    
    

    yes

    
    
    

    no

    
    
    
    
13. Look at the seesaws below, each holding three eggs. Two of these seesaws would tip, and one could balance. Which one could balance? A, B or C?