Movin' Around

If you saw the title of my post today and thought that I was going to start talking about dancing, you are sadly mistaken.  I'm afraid that dancing doesn't really have to do with physics... or maybe it does.  If you fall, that has to do with gravity, and that's physics, right?

Anyway, now that I've gotten completely off track, let me start over.  This week in class, we started to learn about movement.  Again, it's not the dancing kind, it's the buggy car kind!

Let me explain before you go around thinking I've gone completely nuts.  All I mean, is that this week, we did the Buggy Car Lab!  Sounds like a fun name, right?  So far, I think this has been the best lab.  However, I think that's mostly due to the fact that all of the other labs have been kind of basic and not much about moving around.  They were mainly about measurements.

On the other hand, this time, we were asked, "What relationship exists between the time the buggy runs and its position?" This meant that we would get to work with a little car and measure how far it would go in a certain amount of time.  I must admit, it isn't too bad for a lab, although I'm still looking for something with a little more pizzazz.

The Process

Before we began, we had to figure out how in the world we were going to do this lab.  Of course, we were left to ourselves to figure this out, so we started talking.

As a group, we decided to run the buggy by and meter stick and some tape.  For every five seconds we were to make a mark at the point where the buggy was at.  Afterward, we decided to measure the distance from the starting point to each of the marks.  However, there was a catch.  Our teacher decided that we had to do this all in one continuous run.  That being said, we weren't allowed to stop the buggy and make the mark.  We had to do it while it was moving.

Surprisingly, it actually wasn't that hard.  We got it done in record time, but just when we thought we were done, our teacher gave us another task to do.  We were now to start 40cm. behind our original starting point.  This wasn't really hard either, as you may have guessed, and again, we finished quickly.  The only problem was our data.

Got 99 Problems, What to do With Our Graph, Sadly, is One

First and second sets of data on the left and graph on the right.

We weren't really sure what to do with it.  Of course, all the information was right, but we weren't sure if we should add the data point (0,0).  As a group, we decided that for the first set of data, we should use (0,0) because it makes logical sense.  If you are at the starting point and your time is 0 seconds, then you obviously haven't moved from that point, so you are also at 0cm.  On the other hand, for the second set of data, the buggy was 40cm. away from the starting point, so at the time of 0 seconds, the buggy was at 40cm. 

We still weren't sure about this predicament, especially for the second set of data.  Then came the graph problems.  The first graph for the first set of data was obvious because the data increased at a constant rate, but for the second graph with the second set of data, we weren't sure if we should make the first two points at -40cm. and -5cm., or at 40cm. and 5cm.

This is probably the point at which I should explain the idea of reference point and position.  Reference point it the point at which, by looking at it, you can tell that the object moved.  For example, if your friend is standing 2 meters away from the whiteboard and then he moves so that he is now 5 meters away from the whiteboard, you know for a fact that he moved because he is now 3 more meters away from the whiteboard than when he started.  In this scenario, the whiteboard was your reference point because you saw that he moved 3 more meters away from it. 

For position, you must use your reference point.  Let's say that your reference point is the place where another person started.  If that person moved 10 meters North of that point, his position is now 10 meters North of that point.  Basically, position involves the distance away from the reference point, as well as the direction which the object traveled.

To relate all this to my lab, we weren't sure if the distance or postion from the reference point (or the starting point) would be -40cm. and -5cm. for the second set of data because it was in the opposite direction.  In the end, my group decided to go with positive, for now.

Graphing

This time around, our first set of points was graphed as a linear, direct, and proportional line, but our second set of points seemed to look like an absolute value graph.  We will have to bring this up, as well as the other controversial topics, in our next class discussion.

Reflection

This week, I have decided to try a new idea. I have begun to ask questions during our class discussions, even if I already know the answer. I think this will help me, as well as my fellow students.  Also, I am still doing well at participating and understanding the topic at hand.  Movement doesn't seem like a topic that will be very hard to pick up.  The only really odd thing to me is that, last year when I took physics, I don't remember going into so much depth in the idea of movement.  Is this better for me?