# Experiment Report: Water Conductivity Level in Goa Gajah

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• Topic: Water, Body of water, Electrical conductivity
• Pages : 5 (1159 words )
• Published : September 22, 2008

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Experiment Report

Title:
Water Conductivity Level in Goa Gajah

Research Question:
How high is the water conductivity level of the water sources in Goa Gajah?

Hypothesis:
I predict the level of electrical conductivity of the water sources in Goa Gajah will be between the range of a normal drinking water, which is 0.0005 to 0.005 s/m. This hypothesis is based on the fact that conductivity largely concerns itself with the amount of salt in the water, and since none of the water sources are connected to the sea and pretty much well preseved there shouldn’t be too much salt in the water.

Variables:
Independent Variable: The different water sources in Goa Gajah Dependent Variable: Water conductivity
Incidental Variable: Water conductance
Controlled Variables: Water container used, Distance between zinc strip and copper strip

Materials:
-Copper strip
-Zinc strip
-Basic meter (voltage, current)
-3 Alligator clips
-1.5 V Battery
-Water container
-Water samples
-Cellophane tape

Method and Procedure:
1.Connected the copper strip to a battery using an alligator clip. 2.Connected the battery to a basic meter using another alligator clip. 3.Connected the zinc strip to the other end of the basic meter. 4.Placed the copper and zinc strip on opposite sides of the water container. 5.Measured the current and voltage of the water sample.

6.Wiped the copper and zinc strip of any water residue from the sample. 7.Measured the current and voltage of another sample of water. 8.Repeated step 6 and 7 until all the samples were measured

Standardizing the Dependent Variable
To standardize the dependent variable all of them will be processed by multiplying their conductance with the distance between the copper and zinc strip and then dividing the result with the cross-sectional area to get its electrical conductivity.

Manipulating the Independent Variable
To manipulate the independent variable different samples from different water sources will be used.

Maintaining the Controlled Variables
To maintain the controlled variables all the apparatus that are used will not be changed between samples, extra precaution are also taken concerning the distance between the copper and zinc strip so that they remain the same.

Data Range:
-Maximum current: 0.0046 A
-Corresponding voltage: 2.3 V
-Minimum current: 0.0042 A
-Corresponding voltage: 2.1 V
-Distance between copper and zinc strip 0.065 ± 0.001 m

Raw Data:
Water Sample1 (± 0.1 V)1 (± 0.0001 A)2 (± 0.1 V)2 (± 0.0001 A)3 (± 0.1 V)3 (± 0.0001 A)4 (± 0.1 V)4 (± 0.0001 A) Trial 12.30.00462.10.00422.30.00462.10.0046
Trial 22.20.00462.30.00452.20.00442.20.0044
Trial 32.30.00462.20.00432.30.00442.20.0044
Average2.30.00462.20.00432.30.00452.20.0045
Note: 1=Sample 1=Fountain A
Note: 2=Sample 2=Fountain B
Note: 3=Sample 3=Pond
Note: 4=Sample 4=Water Stream

Computations
Relative Uncertainties

Fountain A
Voltage: (0.1 / 2.3) * 100% = 4.35%
Current: (0.0001 / 0.0046) * 100% = 2.17%

Fountain B
Voltage: (0.1 / 2.2) * 100% = 4.55%
Current: (0.0001 / 0.0043) * 100% = 2.33%

Pond
Voltage: (0.1 / 2.3) * 100% = 4.35%
Current: (0.0001 / 0.0045) * 100% = 2.22%

Water Stream
Voltage: (0.1 / 2.2) * 100% = 4.55%
Current: (0.0001 / 0.0045) * 100% = 2.22%

Distances between copper and zinc strip
(0.001 / 0.065) * 100% = 1.54%

Conductance
G = 1/R = I/V
G = Conductance
R = Resistance
I = Current
V = Voltage

Fountain A: (0.0046 ± 2.17%) / (2.3 ± 4.35%) = 0.002 S ± 6.52% Fountain A: 0.002 ± 0.00013 S
Fountain B: (0.0043 ± 2.33%) / (2.2 ± 4.55%) = 0.0018 S ± 6.88% Fountain B: 0.0018 ± 0.00012 S
Pond: (0.0045 ± 2.22%) / (2.3 ± 4.35%) = 0.002 S ± 6.57%
Pond: 0.002 ± 0.00013 S
Water Stream: (0.0045 ± 2.22%) / (2.2 ± 4.55%) = 0.002 S ± 6.77% River: 0.002 ± 0.00014 S

Conductivity
A = πr^2
A = Cross-sectional area