Name: Giang Nguyen
Date: 12/9/2012
Science 7
Designing a Fair Test
When a ball is dropped from a height it will bounce.
THINK: What variables can affect the time a ball will bounce?



Surface
Size of the ball
Person Dropping



Mass of ball.
Shape of ball
Materials
Task: With a partner, choose a variable from the list above and Design, Test and Evaluate an
experiment to find out if and how your variable will affect the height a ball will bounce.
Each student will write their own Lab Report with the following sections:
Comment [SL1]: Thanks for putting your name
and due date on the assignment.
A. Title and date
Comment [SL2]: Good start at title. Can you
Each surfaces affect the height of each ball bounces from the different surfaces.
Due: 24th September 2012.
B. Aim/research question
Comment [SL3]: Unclear
Do the different surfaces affect the time and ball bounces each drop?
C. Variables
Table 1: Variables of the investigation
Identify the variable(s)
How will the variables be changed, measured or
controlled
The ball will be dropped on each different
surfaces six times.
Independent variable
Different surfaces
Dependent variable
Time taken for the ball to
drop
The variable will be measured by a stopwatch.
Each time the ball gets dropped down it will be
timed on how much seconds it needs to go
down to the surface.
The person who drops the
ball
The person who drops the ball will be the
same throughout the experiment as different
people may exert different forces.
Controlled variables/
constants
Stopwatch
The stopwatch must keep the same throughout
the experiment because other machinery may
cause something wrong to the results.
Starting point (where the
ball is dropped from)
The starting point must be the same
throughout the experiment to keep a fair test
as different starting points may affect the data.
The same volley ball
The same volleyball will be used throughout
the experiment in order to ensure a fair test.
Comment [SL5]: Round to the first decimal
place.
Comment [SL4]: Stop bouncing?
Comment [SL6]: Good
Could you have included your criteria for stopping
the timer. Absolute stillness? Bounces over 3 cm?
How did you know when to stop the timer
D. Hypothesis
If the ball gets dropped on different surfaces each time then the time will be not similar
because some of the energy of a falling ball gets absorbed by the surface that it falls on.
Comment [SL7]: Quantitative data in your
hypothesis would make it more testable
It’s not measurable because we can’t measure the amount of energy that is used for the
surface. The used energy, since it came from the ball, it’s not obtainable for the ball to bounce
on the surface. Like a ball gets dropped on the concrete it will bounce higher than on the wool
material because the concrete absorbs tiny amount of energy from the ball, while the wool
material absorbs all the energy from the ball so there will be less bounces or no bounces from
it. The ball also has elastic, elastic is when the ball is bounced its former size and shape will be
pressed down or being stretched. Like a rubber ball for example, rubber is the most elastic
substance; when it’s being pressed down its perfect roundness will be squeezed down on the
surface but instant when you loosens the grabbing it will bounced back into its shape.
Comment [SL8]: ? This part is unclear.
Comment [SL9]: This is very good!
Comment [SL10]: Another very good part
E. Equipment and material
1.
2.
3.
4.
5.
6.
7.
8.
9.
Meter Stick
One Volleyball
Wooden Board
Wool material.
Concrete surface.
Metal board.
Grass area.
Yoga Matt
Stopwatch
F. Method
1. Take all of the equipment’s that are required
2. Find the first surface to test the height for each drop (trial)
3. Use the meter stick ruler and place the stick perpendicular to the ground
4. Hold the volleyball on top of the stick
5. Using a stopwatch and time the volleyball when it hits the ground
6. Drop the ball while observe how it drops down to the surface
7. Stop the stopwatch when it the ball stops bouncing
8. Then record the data from the stopwatch
9. Change all the data into (seconds) and round them to the tenth place.
10. Repeat the steps for three trials for each surfaces (wooden board, wool material,
concrete surface, metal board, grass area and yoga mat)
G. Diagram of
apparatus
Comment [SL11]: This is the tricky part. When
can you tell the ball has stopped bouncing?
Comment [SL12]: Nice!
H. Observations
Table 2: Table showing time taken for different surfaces
Wooden
Wool
Concrete
Board:
Material :
surface:
st
1 Trial
5.8
1.1
5.3
(Sec)
2nd Trial
5.7
1.2
5.6
(Sec)
3rd Trial
4.8
1.1
4.9
(Sec)
Average
5.4
1.1
5.3
Comment [SL13]: Wow!
Metal
Board :
4.2
Grass
Area:
1.7
Yoga
Mat:
2.8
4.1
1.6
3.1
4.2
1.4
3.6
4.2
1.6
3.2
Qualitative:
Yoga Mat: Dark blue, matt, bare, long, thickened.
Wool Material: Lumpy, tufts, fluffy, fuzzy, scratchy, tacky
Concrete Surface: Grey, ripened, brittle, grown.
Metal Board: glossy, metallic, silver, lustrous
Grass Area: smooth, green, light, lush, feathered, dewy, fresh
Wooden Board: timeworn, natural, strong, solid, carved, grainy, rough
I.
Processing and presenting data
A perfect chart!
Comment [SL14]: You just needed to show one
transforming equation.
Comment [SL15]: What title could you have
given your table to make it clearer?
Comment [SL16]: Good graph but the title could
be clearer.
Time taken for each surface
Time of what?
7
6
Time(sec)
5
4
1st Trial (Sec)
3
2nd Trial (Sec)
2
3rd Trial (Sec)
1
0
Wooden
Board:
Concrete
surface:
Metal Yoga Mat:
Board :
Grass
Area:
Wool
Material :
Type of Surface
J.
Conclusion
Different surfaces affect the time and ball bounces for each drop. The wooden board is
a solid material, a solid material (or surface) absorbed a little energy so the ball can
bounce a lot more and the time will be extended; so as the metal board, concrete
surface, and yoga mat. Softer materials absorbed a lot more energy so the volleyball
bounces a bit or maybe not even bounce so the time is will be lesser than the solid
surfaces.
The trends in the data showed that the time for each surfaces is decreasing and doing
it. The wooden board is the highest so it took a lot of time to make the ball stop
bouncing. The second highest is the concrete surface; the difference between the
wooden board and the concrete surface is that the wooden board is the time is higher
by one second. So on down to the metal board, yoga mat, grass area and wool material.
The results support the hypothesis because the data shows that the wooden board
takes the most time, whereas wool material takes the least. The hypothesis states that
solid surfaces absorb insignificant amount of energy and softer surfaces absorb more
energy. It is evident that the hypothesis is correct because the data demonstrated the
time of the ball being dropped for solid surfaces are longer because they are denser;
whereas, the time of the softer materials are shorter because they are less dense.
All surfaces have both equivalent and different responses. Some material will have
equivalent responses which it means the volleyball will bounce up when it’s been
dropped. Where different responses, the ball will not bounce up because it doesn’t
Comment [SL17]: Great term!
Comment [SL18]: Use specific examples from
you data to back up your argument that you
hypothesis was or was not supported.
Comment [SL19]: Is wood denser than concrete?
have enough force to push the ball numerous times such as the grass area it doesn’t
have enough strength or force to push the ball up.
Comment [SL20]: Very interesting! Great job
researching.
K. Evaluation
My hypothesis is valid because my hypothesis has both independent like the surfaces
and dependent like the time taken. The hypothesis supports data and it’s also based on
it. It states how the independent variable affects the dependent variable.
The method is nearly valid too because it’s very detailed and accurate for the reader to
understand. The method includes all the tasks that are required. What I think is
incorrect was I didn’t explain clearly about who needs to take responsible on using the
stopwatch and not showing the person who drops the ball.
Weakness:
Only doing three trials
Improvement:
More trials will be done in order to get
more accurate results as it will show
accuracy. By doing so, it is ensured that
the data is reliable.
Only using one type of ball
Instead of using one type of ball
(Volleyball) we could just use more to see
the different reactions from the different
balls.
The same person will drop the ball
throughout the experiment in order to
ensure a fair test.
Different people dropped the ball
throughout the experiment; therefore, the
force may apply differently or drop at a
different height.
Comment [SL21]: Unclear
Comment [SL22]: Personal pronouns?
Overall good
Comment [SL23]: Excellent!
Criterion B: Inquiring and designing
Student’s Teacher’s
opinion
decision
0
0
Descriptor
The student does not reach a standard
described by any of the descriptors given
below.
The student:
1-2
3-4
5-6
1-2
3-4
5-6
What will this look like in my work?

attempts to state a problem or
question
 attempts to outline a testable
hypothesis
Theisstudent:
able to outline variables
 Attempts to design a method.
 is able to state a problem or
question
 is able to outline a testable
hypothesis using scientific
reasoning
 is able to outline how to
manipulate the variables, and
The student:
state how relevant data will be

is
able to outline a problem or question
collected

to outline and explain a testable
 is
Isable
able
to design a safe method
hypothesis using scientific reasoning
in
which
he orhow
shetoselects

is able to identify
manipulate the
materials
variables,
andand
outline
equipment.
how sufficient ,

relevant data will be collected
Is able to design a complete and safe method
in which he or she selects appropriate
materials and equipment.













The student:


7-8
7-8


is able to outline a problem or question
and justify the selection
is able to outline and explain a testable
hypothesis using correct scientific
reasoning
is able to describe how to manipulate the
variables, and identify how sufficient,
relevant data will be collected
Is able to design a logical, complete and
safe method in which he or she selects
appropriate materials or equipment.



I tried to write the aim for the
investigation
I tried to write a hypothesis
I listed some variables, but my
table is incomplete
I tried to write a method but
My
aim
is stated
there
were
many steps missing
Iand
have
written
my hypothesis but
it was unclear.
it is not explained clearly
I have recorded most variables
and stated how they are
manipulated or controlled. I have
stated how I collected data for
my dependent variable.
My aim gives a brief account of my
My
method is safe and mostly
investigation about bouncing.
complete.
may
have
missed
My
hypothesisI is
in the
correct
format (if,
then,
because)
and is explained
using
some
equipment
and materials.
scientific ideas.
I have recorded the variables and briefly
explained how they are to be controlled and
manipulated. I have outlined how I collected
data for my dependent variable.
My method is complete and I have chosen
the appropriate materials and equipment.
My aim gives a brief account of my
investigation and why my experiment is
relevant.
My testable hypothesis is in the correct
format (if, then, because) and is explained
fully using scientific reasoning.
I have correctly identified all variables and
explained how they would be manipulated
and controlled. I have identified how I
collected sufficient data for my dependent
variable.
My method is complete, reasonable and is
sequenced in the correct order. I have
chosen appropriate equipment
Criterion C: Processing and evaluating
Student’s
opinion
Teacher’s
decision
0
0
1-2
3-4
1-2
3-4
Descriptor
The student does not reach a standard described by
any of the descriptors below.
The student:
 is able to collect and present data in numerical
and/or visual forms
 is able to accurately interpret data
 is able to state the validity of a hypothesis based on
the outcome of a scientific investigation
 is able to state the validity of the method based on
the outcome of a scientific investigation
 is able to state improvements or extensions to the
method.
The student:
 is able to collect and present data in numerical
and/or visual forms correctly
 is able to accurately interpret data and describe
the results
 is able to outline the validity of a hypothesis based
on the outcome of a scientific investigation
 is able to outline the validity of the method based
on the outcome of a scientific investigation
 is able to outline improvements or extensions to
the method that would benefit the scientific
investigation.
What will this look like in my work?
 no data table or graph
 no conclusion
 no evaluation
 I include some data but it is poorly written and
missing important aspects.
In my conclusion
 I state correctly if my hypothesis is supported
or not
In my Evaluation:
 I state if my hypothesis is testable or not
 I state if it was a fair test or not
 II try
and
state some
to the
have
collected
and improvements
recorded data but
there
method
are parts missing in my data table and graph.
In my conclusion:
 I described my results and stated how my
hypothesis was or was not supported by using
data to back up my argument.
In my evaluation:
 I briefly discussed how testable my hypothesis
was.
 I briefly described one reason whether or not I
thought the investigation was a fair test.
 I briefly listed improvements to the method
 My data table and graph are in the correct
format.
5-6
5-6
The student:
 is able to collect, organize and present data in
numerical and/or visual forms correctly
 is able to accurately interpret data and describe
results using scientific reasoning
 is able to identify the validity of a hypothesis
based on the outcome of a scientific investigation
 is able to identify the validity of the method based
on the outcome of a scientific investigation
 is able to identify improvements or extensions to
the method that would benefit the scientific
investigation.
In my conclusion:
 I described my results and explained how my
hypothesis was or was not supported by using
data to back up my argument.
In my evaluation:
 I gave a couple of reasons that explained how
valid/testable my hypothesis was.
 I gave one or two reasons whether or not I
thought the investigation was a fair test.
 I briefly discussed improvements or extensions
to the method.
 My data table and graph are in the correct
format. I have also transformed my data.
7-8
7-8
The student:
 is able to collect, organize, transform and present
data in numerical and/or visual forms correctly
 is able to accurately interpret data and describe
results using correct scientific reasoning
 is able to discuss the validity of a hypothesis based
on the outcome of a scientific investigation
 is able to discuss the validity of the method based
on the outcome of a scientific investigation
 is able to describe improvements or extensions to
the method that would benefit the scientific
investigation.
In my conclusion:
 I described my results and explained using
specific pieces of data how my hypothesis was
or was not supported.
In my evaluation:
 I described in detail how testable my
hypothesis was.
 I gave examples of whether or not I thought the
investigation was a fair test. I also described
whether enough data was collected and used
examples to back up my writing
 I described in detail improvements or
extensions to the method.