
This is an image of lava
channels during the eruptions of Pu'u O'o Volcano, Hawaii. The central channel
shown here is approximately 4 meters (13 feet) wide.
S. Rowland/LPI
Group Size:
6
This activity
asks students to form hypotheses on how the factors of volume, slope, and
viscosity will affect the surface area that a liquid covers and then test them
through experimentation. The
activity then asks students to “become” geochemical engineers and think up ways
to slow down, divert, or halt lava flows. In discussion afterward, they will to
connect what they how the properties of liquids they learned about are
applicable to other real-life scenarios.
· State science:
California
Earth Science (1998), grades 9-12
Dynamic Earth Processes:
e. Students know there are two kinds of volcanoes:
one kind with violent eruptions producing steep slopes and the other kind with
voluminous lava flows producing gentle slopes.
California
Investigation & Experimentation (1998), grades 9-12
1a.
Select and use appropriate tools and technology (such
as computer-linked probes, spreadsheets, and graphing calculators) to perform
tests, collect data, analyze relationships, and display data.
·
State
math:
California Measurement and Geometry
(1997), grades 9-12
2.1
Use formulas routinely for finding the perimeter and area of basic
two-dimensional figures and the surface area and volume of basic
three-dimensional figures, including rectangles, parallelograms, trapezoids,
squares, triangles, circles, prisms, and cylinders.
2.2 Estimate and compute the area of more complex or irregular two- and
three-dimensional figures by breaking the figures down into more basic
geometric objects.
After this activity,
students should be able to:
·
Understand and
describe how volume, viscosity, and slope affect the surface area that a fluid
covers.
Each group needs:
·
3
transparencies with a grid of 1cm2 boxes printed on it, 1 graduated
cylinder (at least 10 ml)
·
For the 3
group types:
Group 1: 18 ml soap, small cup
Group 2: 8 ml soap, 1 T salt,
5 ml water, 3 small cups
Group 3: 9 ml soap, 1 pencil,
1 small circular wooden dowel, small cup
|
Word |
Definition |
|
surface area |
the extent
of a 2-dimensional surface enclosed within a boundary |
|
viscosity |
a liquid’s resistance to
flow |
|
slope |
steepness, incline |
Background
The teacher should know about volcanoes and lava
flows, as this is what this activity is simulating. The teacher is encouraged to use this activity in
conjunction with the associated lesson plan: How far does a lava flow go? Surface area in this activity is
determined by counting the number of boxes that the soap covers. Partial boxes should be added together
to make wholes.
Before the Activity
·
Make copies of
instruction handout for students
·
Xerox copy 1 cm2 graph paper
(attachment) onto transparencies
·
Put soap into
containers or squeeze bottles for students to use, gather materials for each
group together (putting materials for each group in a plastic tub together will
keep everything well organized)
With the Students
1.
Demonstrate how
to count boxes to determine surface area by placing a transparency (with the 1
cm2 graph printed on it) on an overhead projector and pouring a
small amount of soap on it.
2.
Divide
students into at least 3 groups (suggested 6 students/ group).
3.
Ask each group
what aspect they want to experiment with
(volume, viscosity, or slope).
There should be at least one group testing each. If there are more than 3 groups,
multiple groups can do the same experiment. Give students instruction handout (attachment) and tell them
to follow the directions for their groups assigned experiment. Each group should write a hypothesis
about how either volume, viscosity, or slope will affect the surface area the
liquid covers. Tell students to make a data table and record their data and
observations.
4.
Let students
perform experiments and help with problems or questions. See attached handout for instructions
to students.
5.
Have students
record their group data on a table on the board in front of the class. Students should determine the
relationship between what they tested (volume, viscosity, or slope) and surface
area of the liquid. They should
write down if their hypothesis was supported or rejected.
6.
After their
experiment, students should move on to part 2 of the activity, where each group
“becomes” a group of geochemical engineers with the goal of finding a good way to stop, slow down,
or divert lava flows from human settlements. Student’s should be allowed to be creative and not worry
about how much a solution will cost or how hard it would be to achieve. Allow students to brainstorm and
write down ideas.
7.
Have a group
discussion (see associated lesson: How far does a lava flow go?).
1). Activity Instructions
Handout:
To download word document,
see associated lesson.
To view html, go to:
http://measure.igpp.ucla.edu/GK12-SEE-LA/Lesson_Files_08/How_Far_Activity_Instructions.htm
2)
Graph Paper_1cm2
To download word document,
see associated lesson.
This activity is very
safe, with no major precautions.
If the teacher wishes to include the option to test the affect of
temperature on surface area, the teacher may want to monitor students when they
are heating up soap in a microwave as soap should not be overheated (only ~ 10
sec is necessary). Students should not ingest soap.
See
associated lesson
Pre-lesson Assessment
Title:
Preliminary questions for students
Ask student the following
questions:
1) Which phase is lava
from a volcano in (Answer: liquid)
2) Do all liquids move in
the same way? (Answer: no, some are fast, some slow)
3) Do you think that
towns/ cities that are close to volcanoes are all at the same risk during an
eruption (Answer: you should expect various answers of why or why not the
students think some locations/ volcanoes may be riskier than others)
Activity Embedded Assessment
Title: Experimentation & data
collection
Make sure that each group
has written down their hypothesis on how volume, viscosity, or slope will
affect the surface area that their lava (soap) covers.
After the experiment,
students should record their data in their own data tables and write it up on
the board for the class to copy down.
Each student should determine and write what the relationship is between
surface area and each of volume, viscosity, or slope. They should state whether their hypothesis was supported.
Post-Activity Assessment
Title: Class-wide analysis of
results & discussion
Ask for a volunteer from
each group to describe what they found from their experiments about the
relationship between the surface area that a liquid covers and its volume,
viscosity, and the slope of the substrate it flowed across. If there are unexpected results,
discuss what could have caused them.
Ask students again, if they think all volcanoes are equally dangerous
(students should realize that danger may depend on how much lava is released,
its viscosity (or how fast it moves), and the slope of the volcano it flows
down). Ask students what they came
up with as “geochemical engineers” to halt or divert the flow of lava (students
should suggest ways to increase viscosity, make the slope less steep, reduce
the volume, among other creative ideas).
Lastly, ask students how the properties of lava they learned about
during the activity are relevant to understanding the movements of other
liquids.
·
For lower
grades, this activity can teach about the conceptually simple topics of how
volume and slope affect the surface area a liquid can cover. It can also be a whole-classroom
activity where each experiment is performed in front of the classroom with
students being called on to do each step.
·
For upper
grades, the activity can be made more difficult by asking students to make bar
graphs of their data or repeat their experiment 3 times and calculate an
average (more time may be required).
The lesson could also be less guided, requiring students to figure out
and record their own methods in order to test their hypotheses. More options for experimentation could
be included, such as the effect of temperature and substrate texture on surface
area.
Additional Multimedia Support
Smith, Michael; Southard,
John B.; Eisenkraft, Arthur; Freebury, Gary; Ritter, Robert; Demery, Ruta. Integrated Coordinated Science for
the 21st Century. Armonk, NY: It’s About Time, 2004. Lesson is adapted from Part A: Area of
Lava Flow, pp. 26.
Source of lava channel image:
http://www.windows.ucar.edu/tour/link=/earth/images/lava_channel_image.html&edu=mid&back=/search/search_navigation.html
Other
UCLA SEE-LA GK-12 Program, University of
California, Los Angeles.
Developers:
Brittany Enzmann and Marschal Fazio.
This activity was developed as part of the UCLA Science and Engineering
of the Environment of Los Angeles (SEE-LA GK-12) program and has been classroom
tested in several 9th grade Integrated Coordinates Science classes
at University High School in Los Angeles.
© 2009 University of
California, Los Angeles. This digital library content was developed by the UCLA
SEE-LA GK-12 program under National Science Foundation grant number 0742410.