1. What is the volume of a hula hoop?
11mm
2mm
16mm

2. Outer cylinder:
V = πr2h
V = π x 82 x 11
V = 704π
V = 2212 mm3

3. Inner cylinder:
V = πr2h
V = π x 62 x 11
V = 396π
V = 1244 mm3

4. Hula Hoop V = Outer V – Inner V
V = 968 mm3
( = cm3)

5. Can you calculate the density of a Hula Hoop?
Average pack contents: 32 hula hoops
Average pack weight: 25g
Vhulahoop = cm3
Water has a density of 1g/cm3, so this means hula hoops should float.
Weight of a single hula hoop:
25/32 = 0.781g
Density = weight / volume:
0.781/0.968 = 0.807g/cm3