What labels need to be added to graphs?

Answer 1

The X and Y axis need to be labelled (variable name and unit). The graph has to be given a title (usually in the form of the y-axis title vs. x-axis title) and usually a figure number and caption need to added below the graph which can then be referred to in the body text of any report you may be writing.

Normally when plotting experimental data the independent variable (the variable you had control over) is plotted on the x-axis and the dependant variable (the value you measured) would be plotted on the y-axis.

For example, if you were allowing an object to roll down a slope for varying lengths of time (in seconds) and measuring the distance the object travelled in the specified time (in metres), your independent variable would be time (as you choose how long to allow the object to travel for) and so would be plotted on the x-axis and your dependent variable would be distance (as you are measuring how far the object has travelled in a specific time) and so is plotted on the y-axis.

The graph title would be "Distance vs. Time", the x-axis title would be "Time (s)" and the y-axis title would be "Distance (m)". Finally the figure caption may take the form:

Figure 2: Plot of distance an object travelled down a slope vs. time taken.

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