Equipotential Lines and Electric Field Lines

June 18, 2012 - 2nd Meeting of Physics 102.1 Lab

It's been a while since I've done experiments in a physics lab. From mechanics and kinematics, we are to examine the world of electricity and electromagnetism. Our whole physics 102.1 lab journey starts with tracing electric fields through equipotential lines. 

The equipment are new, the style of gathering data is new, and the way we conducted the experiment is surprisingly new. We are to trace equipotential lines in an electrolytic tank where two different electrodes are placed. The set-up is rather confusing, and judging from the way the coordinate system is configured, we are caught up in an array of disastrous coordinates. We started the experiment slowly, but as we figured out the way we would approach the experiment, a swift wind blew throughout our process. We managed to finish the data gathering, although inconsistencies are still seen. 

After the experiment, we are to produce a technical report summarizing the data we gathered. 

- Bartz, 2012

Balancing Objects: A New Perspective

Feb 13, 2012 - 9th Meeting of Physics 101.1 Lab

We all know the concept of balancing, a way of seeing equilibrium. We used the word "balance" significantly in the course of our lives: from eating a balanced diet, to understanding the balanced universe. The term is at its utmost importance to us people. But then, what is the logic behind this phenomena, the process of balancing objects? Why is it possible for systems to achieve an equilibrium, static equilibrium so-to-speak. This unusual question is what we tried to solve during the experiment we had in the laboratory. The experiment is about static equilibrium, center of mass, and their application to some set-ups.

The activity contained four experimental parts. The first one is the easiest, which is to determine the center of mass of a regular object, a meter stick (as the beam in the set-up) specifically. Then, we determined the mass of an unknown object (an external drive we got from my bag) using the set-up from the first one. We added to pans and weights to experimentally measure the mass of the unknown object. In the last 2 parts, we determined the validity of using center of mass to determine the mass of an object, whether it is regular or irregular. 

During the course of our experiment, we had a hard time on finding the center of mass of the beam. It is because of the beam being "unstable" when it comes to balancing. Nevertheless, we got an almost accurate measurement, which astonished our lab instructor. I guess our balancing skills really paid-off during that time. 

That's the conclusion of our last experiment. We are to discuss our plans for the last experiment: the creative project. - Bartz,2012

Oscillation: The Varying Forms

Jan. 30, 2012 - Feb. 30, 2012 - 7th and 8th Meeting of Physics 101.1 Lab

After a tedious experiment about projectile motion, we started to construct our own set-up to verify the different aspects of harmonic oscillation. The only thing that made this experiment hard to digest is the fact that we can't be certain in every observation that we can get. Each value can yield different results, which may stray to the theoretical value of the period of the set-up. Getting into these things made us prepare for the future experiments of the world of physics.

Let me tell a little of oscillation. Oscillation is the repetitive variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. The process can be examined in different forms: by a spring mass system, a simple pendulum, or a physical pendulum. For me, the easiest to observe is the simple pendulum, since the set-up requires a little work to be done. 

The lab was noisy because of the noise made by falling mass samples. Our spring was too loose, which our experiment hard to observe. Nevertheless, we managed to get what we want: the data to prove our hypothesis. This and all that, I say, that our experiment was done profusely, although human errors and uncertainties were floating in the overall observations. The technical report to be submitted will be hard to do, since we got three experiments at hand. - Bartz,2012

Projectile Motion

Jan. 23, 2012 and Jan.30, 2012 - 6th and 7th Meeting of Physics 101.1 Lab

Our first experiment that requires our own design of the experimental set-up was done during these meetings. The experiment examines projectile motion of different particles in different media. This activity was done outside because of precautionary measures. But before we engage into the activity, we had to answer the pre-activity worksheet, which discusses the factors that affect the trajectory of a particle. Nevertheless, it was an easy job to do since we had our classroom discussion about projectile motion.

The first set-up requires a projectile that shoots a metal ball at a distance. The projectile gun was hard to set since we need to check for every parts that may cause any injuries. In addition to that, our ramp was too loose, that it made setting the angle tedious for us. But, in spite all of these hard activities, we managed to finish the set-up and carry on with our experiment. Here are some pictures that we shot during the experiment:

 
    

We also had to examine the motion of a marble upon traversing a slender ramp, which cause a projectile motion at the end of the ramp. Then, a practical test was done on the next meeting, in which we used our calculations to ensure that the projectile will hit the bull's eye of a target. We hit the bull's eye at our first trial, but failed at the second one, because of human error. Although it was close, we are happy of what our calculations came out to be.

This activity is the first of many, which in fact, makes physics a more enjoyable subject than any other fields.

-Bartz, 2012

Using Statistical Data and Graphs (Part II)

Jan. 8, 2012 - 5th Meeting of Physics 101.1 Lab

This is the continuation of my post about using statistical data and graphs. In this part of the lecture, we studied the use of Scatter or X and Y Graph. A scatter plot or scattergraph is a type of mathematical diagram using Cartesian coordinates to display values for two variables for a set of data. Unlike linear graphs, the scatter plots only the points and connects them in an uneven manner.

Here's the scatter plot that we have done during the experiment. The experiment describes the movement (position, velocity, and acceleration) of a ball which is thrown upward on a remote sensor. Graphical results are propagated from the vernier lab quest.

Then, we also had an experiment that examines the motion of a linear particle (like a ruler) through a photogate, an instrument that somehow measures the motion of a particle. These are our results: 

The results shown here are represented by a line with bars on their edges, that indicates uncertainty.

The experiment was a first: a preparation for the next activities. Although it was a little tedious, the experiment was done enthusiastically. --Bartz, 2012

Using Statistical Data and Graphs

Jan. 8, 2012 - 5th Meeting of Physics 101.1 Lab

In today's class, we reviewed the different ways to represent statistical data. We studied the different types of Graphs: Pie Chart, Bar Graph, and The Scatter Plot (X and Y graph). We also conducted a little experiment to apply our knowledge of these graphs. These statistical tools are very important in organizing and presenting data not only to the instructor, but also to the viewers of the work.

Let me get started with the Pie Chart. These graphs are very useful in representing data as percentage of a whole. Here is an example of a Pie Chart of my Daily Time Allotment:

Here is the data used:

       Daily Time Allotment          Time (Hours) 

Studying                              7 

Watching TV                       1 

Surfing the Internet               5 

 Eating                                  3 

 Sleeping                               8 

 Others                                  3  

Next, we studied the way to make a Bar Graph. This is used to represent polls, numbers, and votes into statistical graph. Here is an example of a Bar Graph of the favorite colors of students:

Here is the data used:

       Favorite Color      No. of Students 

 Red                  22 

 Blue                  15 

 Green                11 

Black                 6 

Pink                   2  

This is the first part of our lecture. I will be posting another blog that will emphasize the use of scatter graphs on some physics experiment. I am hoping to recieve the data that we recorded from the activity: the measurement of free-fall motion. -Bartz, 2012

The Best Fit Line

Dec. 12, 2011 - 4rth Meeting of Physics 101.1 Lab with a guest teacher

After a rigorous exam in Chem 16, we had our lesson about the best fit line with a guest teacher. It is a line on a scatter plot which can be drawn near the points to more clearly show the trend between two sets of data.When data is displayed with a scatter plot, it is often useful to attempt to represent that data with the equation of a straight line for purposes of predicting values that may not be displayed on the plot.

The professor clear taught us how to organize the data with the proper notations and formulas. Also, statistical methods of central tendency like mean, median and mode, are used to set the best-fit line. - Bartz, 2011