Teacher Instructions 
Phase I: Teacher Instructions:
(see Student Area for detailed
instructions)
1) Prepare the substrate materials and the apparatus beforehand
(see Teacher Prep).
2) Prepare 12 copies of Team
Trial Table and Team Data Table.
3) Assign your students to 6 groups, one per substrate.
4) Assign two substrates per group (students should experiment
with one substrate at a time):
Group 1-Clay, Gravel
Group 2-Sand, Bedrock
Group 3-Wet Sand, Layered
Group 4-Gravel, Clay
Group 5-Bedrock, Sand
Group 6-Layered, Wet Sand
5) Allocate or allow the students to allocate group jobs.
6) Demonstrate how to conduct trials in the experiment,
emphasize the need to realign the pan containing the substrate prior to
each trial.
A) Place pan containing
substrate on clean, flat table surface.
B) Align pan so that
the mass of the pendulum at rest touches the length of the pan at a distance
of 3cm from the table top.
C) Carefully outline
the base of the pan on the table top (pencil, wax marker). One student
should hold the pan in place.
D) Raise the pendulum
in a taut, even arc from the ring. The string should align with 15o
on the protractor for the first trial.
E) Drop the mass.
F) Before the next
trial, the loaf pan should be checked for alignment, utilizing the
marks made on the tabletop. The pendulum should be checked to make
sure that its position is unchanged relative to the pan (ie. it should
hit the 3cm mark on the sideof the pan).
G) Check to make sure
the substrate surface is as level as possible (by shaking the pan, smoothing
the surface, etc.)
H) Repeat the steps
outlined above for 9 more trials.
I) Repeat
the above for 30o, 45o, and so on.
7) Instruct students in filling out Team
Data Tables.
8) Supervise collection of data for first ten trials.
9) Rotate student groups and supervise ten trials for second
substrate. Have students post their data in an accessible location,
perhaps on a chalkboard or an
overhead. It will be necessary
for all students to have all of the class data for use in creating bar
graphs.
10) Graph data, utilizing a bar graph for class data and a line graph
for each substrate tested. The bar graph should compare all of the
substrates tested
(x-axis) and the angles at which the
substrates were tested (y-axis). Each bar should be labelled with
that substrate's stability factor. These graphs can be
created as a class or individually using
posted data. The line graphs should compare angle (x-axis) and stability
factor (y-axis). The line graphs could show
information for one substrate (one line)
or more (up to 6). We suggest that you use an overhead projector
and overlap line graphs for each of the substrates,
acilitating comparison of data.
11) Discuss bar and line graphs. Discussion should include, but
not be limited to, a comparison of the bar graph and the line graph.
Which is more accurate?
Why? It is expected
that two or more substrates will remain stable at a given degree (bar graph)
but will have different stability factors (line graph). It will be
helpful in this comparison to
include the stability factor for each substrate on the bar graph.
A determination should be made as to which substrates are
most/least stable to build upon.
11) Submit data using the forms labelled Collaborative
Trial Tables
12) Access pooled data, available by November 12, 1999.
13) Analyze pooled data, determining (again) which substrates are least/
most stable and creating bar and line graphs comparing the effect (hopefully
present) that
the larger sample size has upon
results. What are your conclusions? Which substrates are most/least
stable? What factors do you think are important in terms
of stability? Are your conclusions
different when based upon pooled data? Why is it necessary
to have a large sample size? What were some possible
sources of experimental
error? ...and so on...
14) Feeling creative??? Try our final
project. Let your class try their hands at building their own
structures capable of withstanding earthquakes!!! Unfortunately,
this may not be as easy as it sounds........
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