Science at Don Valley How Science Works
Precision
How small a measurement is.
Millimetres are more precise than
centimetres because they are smaller.
Science at Don Valley How Science Works
Accuracy
How close a measurement is to its true value.
Science at Don Valley How Science Works
Random errors
Errors caused by factors we can’t
control, like tiny temperature changes in a room. They can also happen if
you make a mistake – like pushing the stopwatch button too early.
Science at Don Valley How Science Works
Systematic errors
Errors caused by inaccurate
equipment, equipment that doesn’t zero properly or by problems with a method.
Science at Don Valley How Science Works
Reliability
If someone else can repeat your measurements and get the same
results then your results are reliable.
Carrying out repeat measurements checks the reliability of your results.
Science at Don Valley How Science Works
Independent variable
The variable you change to see what happens.
Science at Don Valley How Science Works
Dependent variable
The variable that you measure.
Science at Don Valley How Science Works
A fair test
An investigation or experiment where only the independent variable has
been allowed to affect the dependent variable. This means only changing one variable and keeping everything else the same.
Science at Don Valley How Science Works
Validity
Your results must be valid if you are going to be able to draw a conclusion from them. To get valid results you need to carry out a fair test.
Science at Don Valley How Science Works
Continuous variables
Variables that can have any
numerical value. You should use a line graph to show this type of data.
Science at Don Valley How Science Works
Categoric variables
Variables that are described by
labels. You should use a bar chart to show this type of data.
