Definitions
Hypothesis: tentative statement about the predicted relationship between one or more variables
Variable: Measurable conditions
Theory: A system of interellated ideas used to explain a set of observations
Experiment: research method
Principles of scientific treatment:
Good experimental design allows for valid comparison between treatments and also allows us to examine our hypothesis and not the interaction of many factors. The 4 main key factors required are control, randomisation, standardisattion and replication
Accuracy: How close the experimental results are to the 'true value'; often reflected in the perentage error
Reliability: for an experiment to be reliable it must have been repeated several times and similar results obtained. Repetitions reduce the impact of random error however it does not improve reliability. Relibility is also used todescribe sources of information such as primary and secondary
Validity: how relevant the procedure is to the question being investigated
Diagrams: Use pencil and ruler
Tables
When recording data in a table, ensure
1. A heading which is sufficiently detailed which should include the dependant and indepandant variable
2. NEat coumns and rows drawn with a ruler
3. Units included in the first column or row
Graphs
Needs:
Heading, axes with units, scale at least 2/3 of graphing area is used to provide clarity, clear data points with crosses, line/curve of best fit
Note: Exams will often ask questions on how the experiment can be improved. A way to not answer this is by saying 'make sure the electronic balance is accurate' because it is not specific enough. In order to improve on this answer focus on how the experimental design might limit the validity or reliability of the practical. Where are the errors? How ccan we reduce their impacts? Was everything standardised so that the independent variable influenced the dependant variable? Were there adequae repetitions? Did the experiment allow us to measure what we wanted to measure
Also know your HSC verbs
