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Title: Using Benthic Macroinvertebrates To Check The Health Of
The Hudson River In Newcomb, New York
Student Researcher: Lindsay M. Yandon
School Address: Newcomb Central School
Newcomb, New York
Grade: 6th
Teacher: Paul Jebb
I. STATEMENT OF PURPOSE AND HYPOTHESIS:
The objective of this project is to see if the Hudson River in
Newcomb, New York, is a clean and healthy source of water. The
hypothesis is that the Hudson River is clean and healthy.
II. METHODOLOGY:
The macroinvertebrates were collected from the Hudson River at
the inlet of Lake Harris in Newcomb, New York. I took the water
temperature, the speed of the water and I measured the depth of
the water. In order to collect the macroinvertebrates I placed
a net into the water so that it touched the sand on the bottom
of the river. Then I picked up the rocks that were in front of
the net, scrubbed the rock with a brush and the
macroinvertebrates fell into the net.
MATERIALS:
Sieve, net, waders, thermometer, tape measure, glass jars,
alcohol, gloves, clipboard, pencils, brushes, buckets, trays,
magnifying glasses, forceps, petri dishes, glass vials.
LAB WORK:
1) I got back to the lab and put the macroinvertebrates in jars
of 90% alcohol. 2) They were poured into a U.S. standard 30
sieve and picked them apart from all of the other waste. 3)
Then I rough sorted the macroinvertebrates into groups according
to their size, color, and the number of tails. 4) Then I put
the groups into a petri dish and identified and counted the
number of macroinvertebrates in each order. 5) The organisms
from each order were put into vials with alcohol. I labeled the
vials according to where they were found.
III. ANALYSIS OF DATA:
In order to find out if my water is clean, I calculated the
biotic index (Dates, 1997). The number was 3.4. If the biotic
index is 0 - 3.75, there is no pollution problem. This shows my
water is clean.
I also calculated the percentage of macroinvertebrates in
different orders as seen in Table 1.
Table 1
Percentage of macroinvertebrates in different orders
Order Percent
Ephemeroptera (Mayflies) 7
Plecoptera (Stoneflies) 10
Trichoptera (Caddisflies) 60
Diptera (True flies) 13
Coleoptera (Beetles) 10
Oligochaetes (Worms)
Other
IV. SUMMARY AND CONCLUSION:
The purpose of this experiment was to see if my water is clean.
Crayfish, stoneflies, and caddisflies are all good indicators of
clean water and I found all of these in my water. The results of
my experiment show that my hypothesis was correct, the Hudson
River in Newcomb has both clean and healthy water.
I could improve this experiment by taking more samples, sorting
live animals, and doing this project for a longer period of time
V. APPLICATION:
This will be useful to me because now I know how to tell if
water is polluted or not.
Title: The Effects Of Slopes And Weights On The Distance
Traveled By A Matchbox Car
Student Researcher: David Poon
School Address: Fox Lane Middle School
Rt. 172
Bedford, NY 10506.
Grade: 8
Teachers: Dr. Sears and Mr. Karlsson
I. Statement of Purpose and Hypothesis:
I wanted to know if the slope of the ramp and weight of a
matchbox car affected the distance it traveled. Slope is the
measure of the incline on a plane. My hypothesis states that
the steeper the slope, the longer the matchbox car would travel.
Also, if the matchbox car is lighter, I predict that it will
make the car travel a longer distance.
II. Methodology:
First, I wrote my statement of purpose and hypothesis, conducted
some library research on slopes, and developed my hypothesis. I
then took a matchbox car and tied weights to the top of it. The
weights varied from 1 to 5 pennies. All the weights were the
same. The manipulated variables were the slope of the ramp,
which could be adjusted, and the weights placed on the car. The
responding variable was the length of the car's travel on the
floor. The variables held constant were the matchbox car, floor
surface, track in which the car traveled, and the measuring
tape.
I started the experiment by adjusting the slope of the ramp to 2
cm. I then tested the car's traveling distance. I did each run
5 times and averaged the distance traveled. Next, I tied on the
penny weight and tested it five times. I continued this process
for each of the other weights averaging the distance traveled by
the car. After testing the car on a slope of 2 cm, I tested the
car on four different slopes (2 cm, 1 cm, 1/2 cm, 1/4 cm, and
1/8 cm). Each time the tests were done, I recorded the distance
the matchbox car traveled from the end of the track.
III. Analysis of Data
During the tests, I observed that the matchbox car traveled a
longer distance when the slope of the track was steeper. Also,
the matchbox car was swifter in coming down the track when the
track was steeper. As the slope of the track was lowered, the
matchbox car moved slower and traveled less. Meanwhile, I
observed the penny weights placed on the matchbox cars had no
effect on the distance the car traveled off the ramp. No matter
how many pennies were placed on top, the matchbox car traveled
about the same distance as the matchbox car without any weights.
IV. Summary and Conclusion
When the slope of the track was steeper, the matchbox car
traveled farther and faster. The steeper the slope, the higher
the vertical drop is. Due to gravitational pull and
acceleration, the velocity of a falling object increases for
every second it falls. If an object falls from a higher drop,
it takes longer to reach the ground and it attains a higher
velocity. More potential energy results from the higher drop.
So, the lower the slope of the track, the lower will be the
vertical drop. Therefore, a lower velocity can be attained
during the drop time, lessening the speed of the object and how
far it travels.
When penny weights were placed on top of the matchbox car and
tested on the track with a specific slope, the car traveled the
same distance as the lighter and heavier cars. However during
the experiment, I found that the surface friction between the
car, sloping track, and the floor affected the results of the
distance traveled by the car. The distance traveled by the car
on the same sloping track, regardless of its weight, is the
same. This is because different masses dropping from the same
slope ( same vertical drop) will have the same rate of falling.
V. Applications
One possible use of the effect of slopes and weights is in
roller coasters. Usually free falling roller coasters gather up
speed by descending steep slopes. They are pulled up to the
peak of a steep track, then dropped down the sloped track,
building up speed. No matter how heavy the weight of the roller
coaster and the various passengers, it will always travel at a
specific speed. With this knowledge, engineers calculate how to
make the flips and twists during the ride. Therefore, the ride
can be both exciting and safe.
Title: Keeping The Air Environment Clean When You Clean
Student Researcher: Richard Deitchman
School Address: Fox Lane Middle School
Route 172
Bedford, NY 10506
Grade: 6
Teacher: Dr. Sears and Mr. Karlsson
I. Statement of Purpose and Hypothesis:
This experiment will determine the concentration of airborne
dust using different floor cleaning methods. The methods
include different vacuum cleaners and hand cleaning. The
hypothesis is that better filters produce less airborne dust
while cleaning.
I. Methodology:
Materials: 3 different kinds of vacuum cleaners (a Dust Buster,
a regular vacuum cleaner and a HEPA (high efficiency particulate
absolute) filter vacuum cleaner) and two hand cleaning methods
(wet and dry dusting). I also used a known quantity of
household dust spread on a 1 foot by 1 foot section of the
floor. An airborne particle counter that continuously measures
dust concentrations (Lasair 1002 Particle Counter).
Procedure: Spread dust on a floor surface of 1 foot by 1 foot.
Clean up dust each time with different vacuum or hand cleaning
method. Measure airborne dust levels for each method during
cleaning for 5 minutes and for 15 minutes before cleaning. For
this study, measure the airborne dust levels from the middle of
the room, about 2 1/2 feet from the 1' x 1' test area.
Variables: The experimental variable is the different types of
dust cleaning methods. My dependent variable is the airborne
dust levels. My controlled variables are an equal amount of
dust and the experiment will be done in the same place and for
the same amount of time for all five dust removal methods.
Airborne dust levels will be measured from the same location,
too.
III. Analysis of Data:
The analysis compared airborne dust levels of the different
cleaning methods with background levels of dust taken before
each sampling period. To analyze the data, the difference in
the airborne dust levels from background levels, by particle
size, was determined. In Table l, representative particle sizes
of fine dust (0.4 and 0.7 microns) and coarse dust (1.0 and 2.0
microns) were compared.
Table 1
Particles Between 0.4 And 0.7 Microns Above Background
| Dust | Mini | Dry | HEPA | Wet |
| Buster | Vacuum | Sweeping | Vacuum | Sweeping |
| | | | | |
| 10,175 | 58,844 | 94,532 | 34,733 | 6,374 |
Particles Between 1.0 And 2.0 Microns Above Background
| Dust | Mini | Dry | HEPA | Wet |
| Buster | Vacuum | Sweeping | Vacuum | Sweeping |
| | | | | |
| 58,030 | 3,505 | 61,771 | 1,168 | 9,225 |
IV. Summary and Conclusion:
As anticipated, the HEPA vacuum had the one of the lowest
overall airborne dust concentrations. However, wet sweeping
also was effective in keeping the airborne dust levels down.
Although the HEPA vacuum maybe a good filter when dust is
collected in the vacuum, the movement of air around the vacuum
collection point seems to create some airborne dust. The dust
buster and mini vacuum produced airborne dust levels above
guidelines for clean office levels and were near poor office
level guidelines. Dry sweeping also had particle levels that
were in the poor range for offices. It was also noted that the
background airborne dust levels rose during the experiment,
which might be do to increased car and truck traffic around the
building during the day, which let particles get into the air
intake of the building.
V. Application:
Airborne dust particles can cause health problems for people.
When cleaning it would be good to limit creating airborne dust
while getting floors clean. All five cleaning methods appear to
clean the floors. However, this study demonstrates that
purchasing a HEPA vacuum may be worth the additional cost. For
the vacuums tested, the HEPA creates the least amount of
airborne dust while cleaning. If a vacuum is not available or
affordable then, wet sweeping is very effective. This will get
a home or office clean without creating airborne dust. Don't
dry sweep. It doesn't keep the area you are cleaning free from
airborne dust.
Title: The Great Carbon Monoxide Experiment
Student Researcher: Jason Weinman
School Address: Edgemeont Jr/Sr Highschool
White Oak Lane
Scarsdale, N. Y. 10S83
Grade: 7
Teacher: Ms. Russo
I. Statement of Purpose and Hypothesis:
My first hypothesis is that the carbon monoxide in car exhaust
is deadly for the environment. This experiment should
demonstrate exactly how deadly it is. The plants I used were
also part of our food supply, which shows how bad exhaust from
cars can be. A second hypothesis is that carbon monoxide
affects broad leaf plants to a greater degree than narrow leaf
plants because there is more surface area to take in the deadly
gas.
II. Methodology:
I tested my hypothesis by exposing four plants to car exhaust.
I also used four controls. Two plants in each condition were
broad leaf catnip plants and the other two were narrow leaf
chamomile plants.
My controlled variables were the amount of water, the amount of
sunlight, and weather conditions. My manipulated variable was
the carbon monoxide. The responding variables were height in
inches and health of the plants. I exposed the experimental
group to car exhaust by placing them behind the exhaust pipe of
a car. I ran the car for 20 minutes every other day for two
weeks. If those that I exposed all died and my control didn't,
then I would know that car exhaust is deadly to plants. I also
had eight pots of seeds. Four were experimental, the others
were control. If the control all grew, but all the experimental
group didn't, then I would know carbon monoxide kills seeds
before they grew. The plants I grew were all herbs and part of
the food supply.
III. Analysts of Data:
As I suspected, the controls, even in the beginning, grew better
then the plants exposed to the carbon monoxide. All the plants
in the carbon monoxide group died by day 13 except for one
catnip and that one looked like it was about to die any day.
All the controls were fine. This shows how drastically carbon
monoxide can effect the environment. The seeds, on the other
hand grew evenly, and as yet there are no seed differences.
There didn't seem to be any difference between broad and narrow
leaf plants survival rate, as all experimental plants in the
experiment group died.
IV. Summary and Conclusion:
Carbon monoxide has a greater effect on plants than I previously
thought. The carbon monoxide from cars can do serious harm to
our environment. The only problem with my experiment was than
it really was an experiment on exhaust not carbon monoxide
specifically. The fact that there was no difference in the
germination time of the seeds shows that car exhaust only
affects plants after germination. Therefore, I accept my
hypothesis.
V. Application:
This experiment proves that we have to cut back on our use of
cars. We should support the increased use of mass transit,
carpools, and bicycles. The only other reasonable course of
action is that car companies start using filters to cut back the
harmful emissions in car exhaust. The later is unlikely because
it may be far too expensive for the likes of car companies to
implement. Other environmental companies may however produce
such filters. This also shows that we should be very careful
about what gases reach the plants we eat. Car exhaust also has
a major impact on areas that we use to grow food to feed the
world's population.
Title: The Effect Of Acids And A Base On Copper And Zinc
Pennies
Student Researcher: William Siegel
School Address: Edgemeont Jr/Sr Highschool
White Oak Lane
Scarsdale, NY 10583
Grade: 7
Teacher: Mrs. Russo
I. Statement of Purpose and Hypothesis:
My topic is to find out the effect of different dilutions of
acids and a base on copper and zinc pennies. I will test
hydrochloric and acetic acids and sodium hydroxide, a base. I
wanted to find out the effects of different acids and a base on
pennies, and to see if copper pennies would change the way that
zinc pennies would change. I also wanted to see the effects
that different dilutions of the acids and the base had on the
pennies. An acid is a proton donor and a base is a proton
acceptor.
My first hypothesis stated that all the pennies that had a hole
in them and were made out of copper and zinc would have the
entire inside of the penny eaten away, or that the whole penny
would be eaten away. My second hypothesis stated that if the
penny didn't have a hole in it, even if it was made out of zinc
and copper, or just copper, nothing would happen. My third
hypothesis stated that if the penny was only made out copper and
had a hole in it, it still wouldn't change.
II. Methodology
The way I tested my hypotheses is by performing the following
experiment. I used plastic tubes, hydrochloric and acetic
acids, and sodium hydroxide. Then I use water for the dilution,
pipettes for the dilution, 80 pennies, a pencil, and paper. The
manipulated variables in my experiment are the acids, the
dilutions, the type of penny, and if there was a hole in the
penny.
In my procedure, I took the acids and put them into different
containers. Then I did a 1:1 serial dilution from 100%, to 50%,
to 25%, to 12.5% to 6.25% to 3.4%. Then I put the pennies in,
but first I took 20 copper pennies and drilled a hole in them.
I did that to the zinc ones, too. Then, as a control, I put two
pennies, one with and one without a hole in it, in water, and
did the same for the zinc ones. I then recorded my data. I
also had a second control where I left the pennies out in the
air.
III. Analysis of Data:
Overall, the following observations were made.
1. Copper pennies with and without holes: In the acids, the
pennies became clean, and they were more clean in the stronger
acids. In high concentrations of hydrochloric acid, the color
of the acid turned yellow. In high concentrations of acetic
acid, the color of the acid turned blue. In sodium hydroxide,
at all dilutions, the pennies turned black. The sodium
hydroxide solution was unchanged.
2. Copper clad zinc pennies without holes: These pennies
reacted the same as the copper pennies explained above in the
acids. In the base however, the copper surface was dissolved,
leaving shiny zinc pennies behind.
3. Copper clad zinc pennies with holes: These pennies reacted
differently than the pennies without holes. When I first put
the pennies in the acids, the acids started to bubble, and make
a gas. I think the gas was hydrogen gas, but I did not test it
with a match. At the end of the experiment, the penny in the
highest concentration of hydrochloric acid was completely
dissolved. In some of the other pennies the inside was
dissolved, leaving a black precipitate. In the high
concentration of acetic acids the pennies did not dissolve. The
acid turned blue, and there was a black precipitate in them. In
sodium hydroxide, the pennies reacted the same as the zinc
pennies without holes.
4. Controls: The two controls, water and air had no changes,
except for the zinc penny with the hole in it. That one has a
milky white color in the water, and a white precipitate.
IV. Summary and Conclusion:
In conclusion, I learned that the higher the percentage of an
acid or base, the stronger the solution is. I also learned that
copper has a greater reaction to sodium hydroxide than zinc, and
that different acids turn different colors in the presence of
copper and zinc Finally, it is notable that the zinc penny with
the hole was starting to be dissolved. These results took place
over a long period of time.
V. Application:
These studies can help the world by providing people with
information about the effects of acids and bases in everyday
life. The studies help because it shows that acid and bases can
dissolve pipes in our houses. It also indicates that acid rain
is bad and it will eventually dissolve monuments in Washington
D. C. and metal structures in other places.
Title: Oxidation of Metals
Student Researcher: Silvana Alvarez
School Address: Fox Lane Middle School
Route 172
Bedford, NY 10549
Grade: 8
Teacher: Dr. Sears and Mr. Karlsson
I. Statement of Purpose and Hypothesis:
I wanted to find out more about what kind of metal oxidizes
faster and in what liquid. My hypothesis stated that zinc would
oxidize faster than copper or aluminum, and that all three
metals will oxidize faster in vinegar.
II. Methodology:
The materials used are: three types of metals (copper, aluminum
and zinc), five types of liquids (tap water, purified water,
orange juice, vinegar, and alcohol), paper towels, and thirty-
three ounce plastic cups.
The experimental variables are the type of metals, the type of
liquid and the depth at which the metals are going to be placed
in the liquid. The responding variable will be the oxidation of
the metals. The controlled variables are going to be the amount
of liquid in each cup, the room temperature at which the
experiment will be conducted in, and the type and the size of
the paper towel. The size of each metal isn't going to be
controlled because in this kind of experiment it doesn't change
the results that much, and it's very hard to get each of the
pieces to be the same size.
First, I will write my statement of purpose and then my
hypothesis. Second, I will do my experiment. I will place the
cups in an empty bookshelf at room temperature. Next, I will
fill three cups with two ounces of the first liquid, I will
repeat this process for all of the other four liquids. Then I
will submerge a piece of zinc, a piece of aluminum, and a piece
of copper in each type of liquid. I will cover the cups with
plastic wrap, so that the liquid in the cups does not evaporate.
I will also dip a piece of zinc in a liquid and place it on a
paper towel. I will do this for all three metals and liquids.
I will repeat this process daily. I will also have a piece of
zinc, aluminum, and copper on paper towels without doing
anything to them. I will have a data chart where I will write
what happened each day. At the first sign of oxidation, I will
consider it oxidized. For the copper it would be at the first
sight of green, for the aluminum at the first sign of white, and
for the zinc at the first sign of darkness. Each day at eight
o'clock at night I will check to see what is happening with each
metal. I will write anything that I find strange about how the
metals are reacting to the liquids and anything interesting that
I observe about the project. After twenty days or after all the
metals are oxidized I will have finished my experiment. After I
filled the data chart with all my findings, I will take that
information and write a summary, a conclusion, an application,
and then rate the metals.
III. Analysis of Data:
By doing this experiment I found out that the metals that were
submerged in the liquids in the closed container oxidized faster
than the metals that were dipped in the liquids. The controlled
metals were the ones with the least reaction. My hypothesis was
that zinc would oxidize faster in vinegar, it did oxidize the
first day when submerged in vinegar, but the zinc only dipped in
vinegar still hasn't oxidized.
IV. Summary and conclusion:
I found out that aluminum was the metal that oxidized the
fastest because it oxidized in all liquids, in all situations,
and even the controlled aluminum oxidized. The latest day for
the oxidation of the aluminum was the eighth day and those
pieces of aluminum were dipped in purified water and in alcohol.
The submerged aluminum in tap water, purified water, orange
juice, and alcohol all oxidized the first day. The aluminum
submerged in vinegar oxidized on the seventh day. The aluminum
dipped in tap water and in vinegar oxidized on the forth day,
the one in orange juice oxidized on the sixth day and the ones
in the purified water and alcohol oxidized on the eighth day.
The copper submerged in orange juice and the one in vinegar
oxidized on the first day. The copper submerged in tap water,
purified water and in alcohol Satin haven't oxidized. All
copper pieces dipped in all liquids haven't oxidized yet, except
for the one dipped in vinegar which oxidized on the sixth day.
The zinc submerged in orange juice and the zinc submerged in the
vinegar have been the only pieces of zinc to oxidize and they
oxidized on the first day. All the other pieces of zinc
including the dipped and the controlled haven't oxidized yet.
The controlled copper hasn't oxidized yet, but the controlled
aluminum has on it's seventh day.
An interesting thing that I found out was that for the copper
dipped in the vinegar the oxidation was in the copper above the
vinegar, but for the zinc dipped in the vinegar the oxidation
was all on the zinc that was in the vinegar. Both of this
oxidations filled all the part that was outside or inside the
liquid complete. One thing that was strange was about the
aluminum because whenever the aluminum oxidized it created a
dark middle part of a wavy line and the outsides of the dark
lines there was white oxidation. The oxidation for the aluminum
always had a line shape oxidation. Another interesting thing
was related to the copper that was submerged in alcohol, where
the alcohol met the air it created a dark copper line in the
copper and the copper was lighter below the alcohol. Most of
the dipped metals always had spots of lighter or darker metal
colors where the liquid stayed and dried as small drops after it
was dipped.
V. Application:
I can apply what I have learned to my life in different ways.
First, if I ever wanted to store a liquid like orange juice, I
would know that I wouldn't be able to store it in any of the
metals that I experimented on because all the metals oxidized on
the first day when they were submerged in orange juice. Second,
if I ever wanted to fix any pipe in my house, I would know
whether to use aluminum or copper, and I would use copper
because it takes a lot longer to oxidize in tap water than
aluminum. Finally, if I ever worked in different factories,
this experiment could help me decide what type of metal to use
depending on the different kinds of liquids I work with.
Title: Are There Observable Relationships Between Air Pressure,
Temperature, Wind Speed, And Current Weather Conditions?
Student Researcher: William Aber
School Address: Fox Lane Middle School
Route 172
Bedford, NY 10506
Grade: 8
Teacher: Dr. Sears
I. Statement of Purpose and Hypothesis:
I wish to find out how weather is affected by specific
atmospheric differences, such as temperature, wind speed, air
pressure, and current weather conditions. I am interested in
this subject because weather is a constantly changing variable
in camping and hiking, a specific interest of mine. I have no
hypothesis because I believe having a standing position on a
research topic can change my interpretation of data.
II. Methodology:
To gather data for analysis, I needed a barometer, a
thermometer, and an anemometer. Every day, for a period of 11
days, I recorded automatic readings for temperature using the
thermometer, barometric pressure using the barometer, and wind
speed. I then wrote down my findings. I also wrote down a
description of the weather as I saw it. This data was recorded
in the metric system on a data chart and was used to produce
graphs at the end of the study.
The independent variables in this experiment were temperature,
air pressure, wind speed, and weather conditions which were also
the dependent variables because I wanted to find out how they
affect each other. The controlled variables in this experiment
included the equipment used, the place where the data was taken,
and the time of day when the data was taken. I was interested
in knowing if air pressure affects temperature and wind speed,
if wind speed affects temperature, and if air pressure, wind
speed, and temperature affects weather.
III. Analysis of Data:
When l looked at the graphs after completion of the data
collection period, I started to see some patterns between the
variables. It seemed that if barometric pressure increased or
decreased, the temperature of the air followed it and the
weather became more cloudy and precipitation increased. Wind
seemed to be a factor which did not affect any other variable,
but when the barometric pressure dropped the wind speed seemed
to increase. Before this experiment, I believed the wind was
always calm in the morning and that there was more wind at
night, but now I see that is an unfair generalization.
IV. Summary and Conclusion:
The wind which I recorded in my 11 day study did not seem to
change any other variable with its own changes. I believe this
is became the wind is just the traveling of air around and it
only moves present sections of air, not changing them where they
are. In addition, the barometricpressure seemed to have changed
the air temperature. This might be because the density of air
is changed by the temperature and gases are susceptible to heat
and cold more than any other state of matter. The temperature
probably also effected the pressure because as there is more
heat in a gas, it expands and its density decreases, and when
it is made more cold, it may condense and density increases.
These results are not what I expected and I believe that the
experiment should be extended for a longer period of time to
confirm these results and discover other ones.
V. Application:
I hope to use these findings when I go outdoors in order predict
weather changes by using some basic weather instruments. A
barometer and a temperature gauge are all I seem to need to
predict weather changes for 12 hours into the future.
Title: What Kills Bacteria Best?
Student Researcher: Andrew Teodorescu
School Address: Edgemont Jr/Sr High School
White Oak Lane
Scarsdale, NY 10583
Grade: 7
Teacher: Ms. Russo
I. STATEMENT OF PURPOSE and HYPOTHESIS:
The purpose of my project was to determine how effective common
antiseptics are in killing bacteria. My hypothesis is that
hydrogen peroxide, rubbing alcohol and Stridex, an anti-
bacterial soap, are effective agents for killing skin bacteria.
II. METHODOLOGY:
Eleven petri dishes were filled with agar and sterilized on
5/6/98. A sterile swab was touched to my hand and then used to
inoculate the plates. The plates were kept in a warm place and
the bacteria were allowed to grow. On 5/13/98, all the plates
were photographed after the colonies were counted and marked.
Pieces of filter paper cut into 1-cm circles were soaked in
either normal saline (control), hydrogen peroxide (H202),
rubbing alcohol, or Stridex (Stridex). One filter paper was
then placed into each dish. Two of the petri dishes acted as
controls, leaving three dishes for each of the other three
groups.
The next day, the filters were removed and re-soaked while
photographs were taken. The colonies were counted again. After
the photographs were taken, the filters were replaced and the
bacteria allowed to grow for three more days. On 5/17/98, the
filters were removed. The colonies were counted and the last
set of photographs taken.
III. ANALYSIS of DATA:
Only colonies in direct contact with either Stridex or rubbing
alcohol were destroyed. This effect occurred immediately.
No colonies outside of the green circle were killed. The green
circle denotes where the anti-bacterial agent was placed on the
petri dish.
Hydrogen peroxide did not affect the bacteria.
IV. SUMMARY AND CONCLUSIONS:
Rubbing alcohol and Stridex are effective bacteria killers, but
work only with direct application. This effect occurs shortly
after contact. Hydrogen peroxide did not affect the bacteria.
My hypothesis is only partially correct. Rubbing alcohol and
Stridex are effective bacteria killers, but hydrogen peroxide is
not.
V. APPLICATION:
Rubbing alcohol and Stridex can be used to kill bacteria, but
these agents work only where they are applied and cannot be
expected to kill bacteria at a distance. Hydrogen peroxide is
not an effective agent in killing bacteria and should not be
used in this manner.
Title: Does a Steady Hand Get "Shakier" With Age?
Student Researcher: Anne Glazer
School Address: Edgemont Jr\Sr High School
White Oak Lane
Scarsdale, NY 10583
Grade: 7
Teacher: Mrs. Russo
I. Statement and Purpose of Hypothesis
I wanted to find out whether a person's hand gets shakier as he
or she gets older. My hypothesis is that the nerves in your
hand are steadiest when you are young and you lose that quality
with age. This is an important experiment to do, especially for
potential doctors or dentists. Would you want a surgeon
operating on you who is 30 and has steady hands, or someone who
is 60 and has regular hand tremors? (Of course, experience
counts, too. ) This is a very necessary experiment and I am
happy to be doing it.
II. Methodology
I constructed a nerve-tester. It consists of a buzzer, a long
wire with a small loop on the end, another wire with no loop,
and centimeter markings directly under the wire. I asked three
testers in each age category (5-10, 11-15, 16-20, 2130, 3140,
41-50, 51-60, 60 & up) to run the loop through the non-looped
wire. If the two wires touched, the buzzer would go off. I
recorded at which marking the buzzer sounded. Each person tried
three times, and I recorded their individual scores and
calculated an average score. Keep in mind, the lower the score,
the better.
My controlled variables were:
The nerve-tester itself. The straightness of the wire.
The surface the tester was on (it was always on a hard, flat
surface like a desk or a table).
My manipulated variable was the person's age.
My responding variable were the scores each person got.
III. Analysis of Data
After collecting my data, I looked over the results. I computed
an average for each person tested and an average for the overall
age group. When I compared the averages, I found my hypothesis
was almost perfect, with the youngest group scoring the lowest,
and the numbers building higher to the oldest group. The range
of scores were from a low of 1.3 to a high of 8.3. These
numbers represent the points the age group got to on the tester.
The only inconsistent group was the 21-30 year olds, and that
was because one score was very high.
Age Tester No. 1 Tester No. 2 Tester No. 3
Overall Total
Category Average Average Average Average
5-10 1.6 1.3 1.0 1.3
11-15 1.0 2.0 2.0 1.7
16-20 4.0 3.0 1.0 2.7
21-30 3.0 3.0 7.0 4.3
31-40 2.0 1.0 4.0 2.3
41-50 1.0 7.0 4.0 4.0
51-60 3.0 4.0 9.0 5.3
60+ 8.0 7.6 9.0 8.2
IV. Summary and Conclusion
It appears that my hypothesis is correct and that people's hands
get shakier as they grow older. The youngest group of testers,
the 5-10 year olds, had the lowest average at 1.3. The oldest
group of testers had the highest average at 8.2.
I have also concluded that some people have naturally steady or
shaky hands, no matter how old they are. For example, I
personally have a shaky hand and so does my brother. My mother
and sisters all have very steady hands. Not only does it depend
on the age, but it also has a lot to do with the person.
Most people's hands are at their "shakiest" when they are put
under pressure or very nervous. For example, when I tested my
cousin, he scored very well when I tested him with nobody
around. When all the relatives heard the buzzer and came in to
see what was going on, his hand shook more and he didn't score
as well, just because everyone was watching him. Maybe this
needs to be a variable which is controlled in the future.
I therefore conclude that while my hypothesis is correct, age is
not the only factor to play a role in steadiness of hands.
V. Application
I can easily apply this information to real life. Like I
mentioned earlier, the steadiness of your hand can be important
when looking for a job. Some jobs, like doctors, for example,
require a steady hand. Also, steady hands can be important in
playing sports, holding objects, and even writing. Someone in
one of my classes has very sloppy handwriting, and when I tested
him, I discovered that his hand is very shaky. He probably has
trouble holding a pen.
While at the pharmacy last week, I noticed there were large
grips to fit over things like keys, silverware, light switches,
and doorknobs. These are likely designed for older people who
have trouble grasping small objects. I never realized how
important it is to have a steady hand, and I am glad that people
are doing all they can to make it easier for people who don't
have naturally steady hands.