Junction Hill Science Fair
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Transcript of Junction Hill Science Fair
• The Independent variable is the item you are testing within the experiment. • Examples might be: Height of a ramp
Amount of salt
4 cm 6 cm8 cm
1 teaspoon or
10 grams
2 teaspoons or
20 grams
3 teaspoons or
30 grams
• The dependent variable is the item you are using to measure the effect of the independent variable • Examples might be:
60.2 cm
Distance The Car Travelled
Time it takes the salt water to
freeze
Salt Water Ice Cube froze in 27 min 22 sec or
1642 sec
4 cm
Run Distance (cm)
1 145.3
2 146.7
3 144.2
4 147.1
5 145.5
avg 145.8
6 cm 8 cm
Run Distance (cm)
1 157.4
2 159.1
3 158.8
4 157.9
5 158.4
avg 158.3
Run Distance (cm)
1 169.7
2 171.2
3 170.8
4 171.8
5 170.3
avg 170.8Whether we are measuring the distance a car will travel down ramps of different heights, or if we are measuring the time it takes water with different amounts of salt to freeze, the measurements are considered our dependent variable
Amount of Salt (tsp or grams)
Time for ice cube to freeze (seconds)
1 teaspoon or 10 grams 1642 sec
2 teaspoons or 20 grams 1822 sec
3 teaspoons or 30 grams 1983 sec
A list of materials is necessary in case someone wants to perform the experiment
Experiment 1
Experiment 2
Place cardboard on a table
Lift and place one 4cm block under and on one side of the cardboard
Place car at the top of the cardboard ramp
Release car with NO added force
Once car comes to a rest, measure the distance from the bottom of the ramp
to the front of the car
Record the distance and repeat four more times. Calculate and record the
average of the five runs
Repeat steps 2-5 for the 6cm and 8cm block
Place 6 oz or 5oml of water in a jar
Pour 1 teaspoon or 10 grams of salt in the water and stir until salt has
completely dissolved
Pour salt water solution into an ice tray. Be sure to measure the exact
amount and record
Place ice tray into the freezer portion of a refrigerator, close freezer door and
begin recording time as your start time.
Once the ice cube is completely frozen, record the time as your stop time. Calculate the time for the ice
cube to freeze by subtracting the start time from the stop time.
Repeat steps 1-5 for the 2 teaspoon and the 3 teaspoon samples
Height of Ramp (cm)
Avg Distance Car Travelled
(cm)
4 145.8
6 158.3
8 170.8
Experiment 1 Experiment 2
Amount of Salt
(tsp or grams)
Time for ice cube to freeze
(seconds)
1 or 10 1642
2 or 20 1822
3 or 30 1983
A graph is a visual representation which provides a way to easily understand the
data
Dis
tan
ce C
ar T
rave
lled
(cm
)
30
60
90
120
150
180
Height of Ramp (cm)
4cm 6cm 8cm
300
600
900
1200
1500
1800
Amount of salt (grams or tsp)
1 or 10 2 or 20 3 or 30
Tim
e to
Fre
eze
Ice
Cu
be
(sec
on
ds)
2100
Original hypothesis
I think the ice cube with the least amount
of salt (1 tsp) will freeze in the shortest
period of time
ConclusionConclusion
My hypothesis was correct, the ice cube
with the least amount of salt froze in the
shortest period of time. I think the reason this
ice cube froze this quickest is because salt
contains heat energy which slows the rate of temperature change in
the water
Experiment 2
I know a science fair project can seem
overwhelming. I hope this information will be of help.
Just remember to