Sinking Ships

We recently completed an investigation where students experimented how changing variables affected how many passengers their "lifeboats" could hold. Students constructed lifeboats of different sizes out of Styrofoam cups and floated them in tubs of water. We measured boat capacity using syringes and graduated cylinders. After deciding on which variables we needed to control (how the pennies were placed, the condition of the sea, wet vs. dry pennies) they placed pennies in the boats until they sank, recording how many passengers (pennies) their lifeboats (cups) successfully held. Students discovered that the greater the capacity of the boat, the more passengers it held. They graphed their results using a two coordinate graph, and predicted outcomes of future trials by using their graphs.

Important Content Notes/Vocabulary:

• Capacity is the maximum amount of fluid a container can hold.
• A two-coordinate graph displays the relationship between the independent and dependent variables in an experiment.

** Did you know that pennies minted since 1983 are copper-plated zinc? Older pennies are made of solid copper. Because they are made of different metals, the new and old pennies have different masses. All of the pennies used in our investigations were "new" pennies, so that they would have a standard mass.