10-14

Will Powers Pd. 7 Physics  10-14-08 TPJ Today in physics class we took our XT graph quiz and finished our lab using motion detectors. In this lab we had to walk in front of the motion detector in the same way that was shown on the XT graph. Since the XT graph shows time and speed, we had to be very precise in order to make the graphs look alike. After completing all of the graphs, we had to answer questions on the lab such as, “How would you walk in order to make this graph? What is happening to the speed in this graph? How fast is the object moving at 4 seconds?” In order to answer these questions, one must understand what the XT graph is saying and how to read it for what they are looking for. An XT graph is such…

X= Distance (m) Y= Time (s)

An XT graph showing a person walking away from the motion sensor from the reference point at a constant speed would look like this… In conclusion, today was a day devoted to XT graphs in physics. The main thing you need to know about this type of graph is that is a relationship between time and distance, nothing else. You might be saying, “Why is there a side below the line if the reference point is the horizontal line?” This is because we set the reference point 1.5m away from the motion detector in order to make it possible to have a negative distance.