Once your data has been presented in a graph, you will need to work out what the graph is telling you. From the graph, you should be able to see the relationship between the two variables.
A graph will help you to see if or how the independent variable affects the dependent variable.
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Graphs of variables that are directly proportional (Graph 1) and inversely proportional (Graph 2)
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B Graph 1 zz Graph 2
Graph 1 shows a relationship that is directly proportional. If two quantities are directly proportional, as one increases, the other increases by the same factor.
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Graph 2 shows a relationship that is inversely proportional. If two quantities are inversely proportional, as one quantity increases, the other decreases by the same factor.
Forming Conclusions
The last step in the scientific method is forming conclusions. Conclusions are what you found out in the investigation.
Compare what you found out with your original hypothesis. Do your results support the original hypothesis or do they not support it? Either way, you should evaluate your investigation.
To evaluate your investigation, comment on its strengths and weaknesses. z z
Method: consider sources of error in your method and suggest improvements to address these errors.
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Results: ask the following questions: Are the results valid? Do they measure what they were supposed to measure? Are the results repeatable and reproducible?
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Conclusion: your conclusions must be made based on the results of your investigation. You should not include statements that are not supported by the data you have collected.
Remember that there is no such thing as correct or incorrect data or right or wrong answers to scientific investigations. Each investigation generates new information, so even unexpected results have value.
