AQA GCSE Science Glossary of Terms
The terms from the official AQA list that are needed for ISA controlled assessments. (I suggest that while using the learn, mode you try to paraphrase the important points, and if you have them all, then mark your answer as right.)
Terms in this set (29)
A measurement result is considered accurate if it is judged to be close to the true value.
Marking a scale on a measuring instrument.
Information, either qualitative or quantitative, that has been collected.
The difference between a measured value and the true value.
These are values in a set of results which are judged not to be part of the variation caused by random uncertainty.
These cause readings to be spread about the true value, due to results varying in an unpredictable way from one measurement to the next. Random errors are present when any measurement is made, and cannot be corrected. The effect of random errors can be reduced by making more measurements and calculating a new mean.
These cause readings to differ from the true value by a consistent amount each time a measurement is made. Sources of systematic error can include the environment, methods of observation or instruments used. Systematic erros cannot be dealt with by simple repeats. If a systematic error is suspected, the data collection should be repeated using a different technique or a different set of equipment, and the results compared.
Any indication that a measuring system gives a false reading when the true value of a measured quantity is zero. A zero error may result in a systematic error.
Data which has been shown to be valid.
A fair test is one in which only the independent variable has been allowed to affect the dependent variable.
A proposal intended to explain certain facts or observations. (A statement of a belief about what the conclusion of an experiment will be based upon expectation)
The quantity between readings.
Precise measurements are ones in which there is very little spread about the mean value.
A prediction is a statement suggesting what will happen in the future, based on observation, experience or a hypothesis.
The maximum and minimum values of the independent or dependent variables, important in ensuring that any pattern is detected.
A measurement is repeatable is the original experimenter repeats the investigation using the same method and equipment and obtains the same result.
A measurement is reproducible is the investigation is repeated by another person, or by using different equipment or techniques, and the same results are obtained.
This is the smallest change in the quantity being measured (input) of a measuring instrument that gives a perceptible change in the reading.
A line graph, not necessarily on a grid, that shows the general shape of the relationship between two variables. It will not have any points plotted and although the axes should be labelled they may not be scaled.
This is the value that would be obtained in an ideal measurement.
The interval within which the true value can be expected to lie, with a given level of confidence or probability.
Suitability of the investigative proceedure to answer the question being asked. (This requires the suitable control variables to be controlled)
A conclusion supported by valid data (evidence), obtained from an appropriate experimental design and based upon sound reasoning.
These are physical, chemical or biological quantities or characteristics.
Categoric variables have values that are labels.
Continuous variables can have values (called a quantity) that can be given a magnitude either by counting or by measurement.
A control variable is one which may, in addition to the independent variable, affect the outcome of the investigation and therefore has to be kept constant or at least monitored.
The dependent variable is the variable of which the value is measured for each and every change in the independent variable.
The independent variable is the variable for which values are changed or selected by the investigator.