Graphs, Tables and Variables
By the end of the lesson you should be able to:1) Draw a results table2) Decide whether a line graph or bar chart is most
appropriate3) Draw a perfect graph4) Remember the important variables words and use them
properly.
-er describing words
faster
brighter
Patterns!
The ______er the ____ the _______er the__________
The ______er the ____ the _______er the__________
The ______er the ____ the _______er the__________
1000cc125cc 500cc
The ______er the ____ the _______er the__________
40p £1.99£4.99
As the ________ increased then the _________increased/decreased/did nothing.
Age
Score in a maths test
As the ________ increased then the _________increased/decreased/did nothing.
Height of the person
Score in a maths test
As the ________ increased then the _________increased/decreased/changed.
Fitness of the person
Time taken to run 100m
How to draw a perfect table
How Science Works
Independent variable
The variable you change to see what happens.
How Science Works
Dependent variable
The variable that you measure.
How to draw a perfect table
I.V. D.V.
• An experiment to see if drinking coke makes me stay awake longer than drinking water.
• An experiment to see which type of fish food makes my fish live longer
• An experiment to see which type of oil makes my car brake faster
• An experiment to see whether boys or girls are better at scoring goals in football
• An experiment to see if Pantene or Herbal Essences makes your hair more shiny
• An experiment to see which type of bait attracts the biggest fish
Graphs
• Continuous variable for IV• Line graph• The perfect line graph looks like…
• Discrete/categoric variable for IV• Bar chart• The perfect bar graph looks like…
Example
Does the temperature of the washing machine affect the percentage of stains removed from my clothes?
10°c = 20%70°c = 5%40°c = 90%50°c = 50%20°c = 50%30°c = 80%60°c = 30%
Odd results
X
XX
X
X
XX
Length of foot
Height of person
How Science Works
Continuous variables
Variables that can have any numerical value. You should use a line graph to show this type of data.
How Science Works
Categoric variables
Variables that are described by labels. You should use a bar chart to show this type of data.
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.
How Science Works
Independent variable
The variable you change to see what happens.
How Science Works
Dependent variable
The variable that you measure.
How Science Works
Control variables
The factors you need to keep the same to make your test fair
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.
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.
How Science Works
Continuous variables
Variables that can have any numerical value. You should use a line graph to show this type of data.
How Science Works
Categoric variables
Variables that are described by labels. You should use a bar chart to show this type of data.
Precise Independent variable
2 marks Random errors
Line graph Accurate Continuous variable
Bar chart
Control variable
Units Valid Dependent variable
Reliable 25% Systematic errors
Fair test
Categoric variable
Take repeats and average
4 marks 24.9887%
Investigation Words Bingo!
• IV• DV• Reliable• Control variables• Control experiment• Accurate• Precise• Fair test• Biased• Valid
KEY WORDS
PreciseIndependent variable Accurate
Random errorsLine graph Causal relationshipContinuous variable Bar chart
Control variable Units Valid Dependent variable
Reliable Systematic errors Fair testCategoric variable Take repeats and average
Correlation
Precise Independent variable
Accurate Random errors
Line graph Causal relationship
Continuous variable
Bar chart
Control variable
Units Valid Dependent variable
Reliable 25% Systematic errors
Fair test
Categoric variable
Take repeats and average
Correlation
24.9887%
Top Related