INSTITUTE FOR INQUIRY
Foam is a material made up of gas bubbles separated from one another
by a liquid film. Foam has physical properties which can serve
as a model for may other phenomena. It also serves as a vehicle
for learning about the complexities of surface area. In the following
investigation, you will explore some of the physical properties
(for each group)
- two 6" desert
size plastic coated plates
- 2 bowls
- 1 teaspoon
- 1 cup (about
- 1 or preferably
2 hand mixers
- one set of
- 1 ruler
- 1 magnifying
spoons or tongue depressors
Put 1 tsp. of Joy or Dawn detergent and 1 cup (8 oz.) of water
in each of two bowls.
Beat each mixture with an eggbeater counting the strokes.
Bowl A 200 strokes
Bowl B 600 strokes
1/ Which foam
has bigger bubbles, A or B?
On the small
plastic plates, build piles of foam as high as you can.
2/ How high a pile can you build with A? How high a pile can you
build with B?
On small plastic plates, build mounds of foam 4 inches high; one
with foam A and one with foam B. Try to make a dowel stand vertically
in the foam, with the pointed end of the dowel down.
3/ Which is the longest dowel that will stand in foam A? Which is
the longest dowel that will stand in foam B?
4/ Which foam is the strongest, A or B?
5/ In the experiments above, what other differences did you notice
between foam A and B?