We began today with a check-in regarding the students’ Boats Essays, which are due on Monday. Then we revisited yesterday’s lab. For any well built boat, one that wouldn’t leak or crumple, could there be a way to calculate how much it would hold?

The answer, of course, is yes! It’s just an application of the density formula!

Using the formula is easier than it looks. First, you weigh the boat to find the mass in grams. Then you calculate the volume of your boat in milliliters. And for any boat, the density just before it sinks is 1.0 g/ml, so you can fill that in too. The only variable you don’t know is “m_c” (the mass of the cargo).

For the next two days in class, students will be attempting to answer the question “How Much Will It Hold?” for seven different objects. They will measure the object’s volume, weigh it, and solve the equation to figure out the maximum mass it could support before sinking. Then they will divide by 60 to try to predict how many of the 60 gram bolts that could be. At the end of class on Monday, we will get out the aquarium and test each of the seven objects to see if their predictions were right.

September 24 – How Much Will It Hold Lab Day #1 (pg115)