Bowling for Density!

 The Chem Co-op class is still collecting density data. My husband’s Physics class is combined with my Chem class this week and next Tuesday.   Today, I checked that everyone had a hypothesis.  Four kids did. (There are 18 students.)  I’m glad I checked.   They must hypothesize which method to determine volume is most accurate.  In one group, the two kids had different hypotheses; one teen thought volume by displacement, the other said using calipers was most accurate.  They’re in the same group!  The kids will use their hypotheses for the lab report.  

Half the kids finished collecting loads of data.  They worked on Bowling for Density! (This link calls in The Floating Bowling Ball.). Below are videos about the activity.  I have several questions I ask when I do Bowling for Density.

1. Will a bowling ball float?  Maybe.

2.  What determines whether a bowling ball will float?  It must be less dense than water.

3.  What is the density of water?  1g/mL or 1 g/cm3

4.  How much does the bowling ball weigh?  Our balls are 10 and 12 lbs.

5.  The bowling ball weighs 10 lbs.  What unit will we use for mass?  Grams.

6.  How will you measure the volume of the ball?  Use the formula for the volume of a sphere and measure the ball’s circumference, which should be about 68 cm.

7.  Once you have the mass in grams and the volume in cubic centimeters, how will you determine whether or not the ball will float?  Divide M/V and see if the density is less than 1 g/cm3.