## Graphing in Physics

**Graphing:**

**How to plot good Science graphs in Excel****Common Graph Forms in Physics****Deriving Relationships from Graphs****Examples of Common Graph Errors**- How Many Data Points are Enough?
- Interpreting Slopes, Areas, and Intercepts of Graphs
**Physical Interpretations and Graphical Analysis****Preparing Graphs**

**Graphing Rules**

Graphs you draw must have the following five basic characteristics:

**1. A Title**- Your title should be short, but still clearly tell what you have graphed.
- The most common and recommended way to name your graph is to say what your "y" (vertical) and "x" (horizontal) axis are.

**2. Labelled Axis**- Make sure to write out the full name of what you have graphed on each axis, along with the units you used.
- If you are using any sort of scientific notation for the numbers, make sure you show it here also.

**3. A Well Chosen Scale**- The information you plot should always cover at least 75% of the area on your graph.
- Look at how big the numbers get on the horizontal and vertical axis, and how much room you have.

**4. The Correct Data Plotted**- It’s too bad when a person does all this work, and then does a sloppy job of plotting their information.
- Make sure you are as careful as possible when marking your points on your graph, otherwise everything else is a waste of time.
- You should always put little circles around each dot, since they might be hard to see on the graph paper. It also shows that each data point is a bit "iffy".

**5. A Best Fit Line**This step is sometimes optional (as you’ll see on the graphs we will be studying here!).

- Usually, you do not want to play “connect the dots” with your plots on your graph.
- Instead, you should try to draw a completely straight line that best fits your data.
- Try to get as many plots above the line as below, so that your line is in the middle.
- This is the line that you will calculate your slope from. Use the formula: