I love to do this lab or one similar to it in person, but you can also conduct an investigation about motion on your own. I’ve created some videos that you can use to collect data (and maybe these will inspire you to setup a situation from which to collect your own data) and I’ve also given you a little bit of video instruction to help out.

Here’s the basic idea: You want to figure out how to characterize motion, but all we can really measure directly is a position (“where”) and a time (“when”). We look for changes in these two things to describe motion.

I’ve just found a pool ball and a smooth table that the ball will roll on. (Like I said, you could do this as well, but it turns out I have a really nice setup for this.) You will want to compile some data about when (time) the ball is in different locations (positions). By getting this motion of the ball on video, you have the ability to repeat the same motion over and over and collect whatever data you need. In this case, I’m suggesting that you collect data for the time it takes to go from the start position of 0cm to another given position. I’ve marked increments of 10cm, so you can get the time it takes to get to the 10cm mark, the 20cm mark, the 30cm mark, and so on. The biggest distance I have marked on the video is 120cm. By replaying the video and running your stopwatch 12 different times, you can get 12 different data pairs of position and time.

I explain this here:

Then, you can jump into collecting data. Start with this video of the pool ball on a flat table. There’s two different versions of the motion, one in real time and the other in slow motion. Just pick one of these.

Like I said, you can pause and go back over and over, each time finding the time it takes the ball to go from 0cm to another mark on the table. Record those times with their corresponding positions in your notebook.

Then, you can do the same with this video of a ball rolling on a sloped table:

Once you’ve made all your measurements, your data can go into a spreadsheet or another table, and then from this you can create a graph. By tradition, and so that we can all compare our graphs to one another, your graph should have the positions on the vertical axis (“y-axis”) and the times on the horizontal axis (“x-axis”). So, a blank version might look like this:

But you’ll be filling this in with your own data. You can do this by hand, of course, but it’s also straightforward to have a spreadsheet (Excel, Google Sheets, etc.) make the graph for you as you input your data. To give you an idea of what I mean and to get you started, here’s a template for a spreadsheet that you can copy or download. You can then edit your own version to your heart’s content. I’ve set this up so that as you input data in the appropriate columns you should see the graphs form magically, all by themselves. You’re also welcome to change the settings for the graph, although I’ve tried to make it so you don’t have to.

Enjoy! I’m excited to see your data and the patterns your data create. You’ll be thinking about why it looks this way and we’ll talk about what this all means. Your assignment will tell you what I’m looking for in your report.