OpenStax College Physics for AP® Courses, Chapter 20, Problem 6 (Test Prep for AP® Courses)

This is College Physics Answers with Shaun Dychko. This data table shows us the voltage and the current across a resistor and we are supposed to plot these on a graph and comment on the shape of the graph and then calculate the resistance. So I am using a Google sheet to put this data into so I have the current column here and the voltage column and then I made a graph of these columns by clicking these graphing button here and then I created a trend line that will tell us the slope as well by going to the the "Series" section of this chart editor and then scrolling down to the 'Trendline' checking that box and then I said 'Use Equation' from this options for the labels. So we have this graph here and it's a linear graph so that answers our question about the shape— it's linear, it's a straight line— and we expected that because the relationship between voltage and current is that voltage is the resistance multiplied by the current and that's of the form y=mx that we are familiar with for the equation of a straight line. Now there's also a plus b here in our slope-intercept form for a straight line but in this case, the intercept is zero. Okay! So a linear graph! And the resistance is the slope of the graph because this R corresponds to m, which is the slope here and the spreadsheet will tell us what that slope is it's 3.6 if you have two significant figures and there we go! 3.6 ohms is the resistance.