On Projectile Motion

January 28, 2011; 8:30-11:30; NIP R108

My friend, Mac, and I were late this meeting because we finished the technical paper on the determination of g which, to our surprise, was not really due this meeting. It was sort of a relief because this allowed us to do some revisions.

When we entered, an experiment was already on its way. It involved a pump that was set to a variable angle and a metal ball was placed on the receiving end. When the pump was released, the ball would be flung and the distance it traveled was measured using a sheet of carbon paper.

The experiment was a display of projectile motion, which is the superposition of x and y motion. This two dimensional motion could be split up into its x and y components since the two are independent of each other. There is no x-acceleration while g is the y-acceleration.

The range (the x-distance) is computed as

X=Vi*cosA*t, where A is the angle of inclination

while the height (the y-distance) is computed as

Y=Vi*sinA-0.5g*t^2, where A is the angle of inclination

Rearranging the terms in the first equation, we can find t and plug it into the second equation

Y=X*tanA-0.5g*(X/(Vi*cosA))^2

The values that we know are X and A, we do not know Y and Vi. We have to perform another experiment to find the value of Y or Vi to completely describe the system.

I was unfortunately separated from my group and was put into another. I really felt uncomfortable with my new group mates because I didn't know them.To add to that, I was not in my optimal setting because I didn't sleep that well the night before. Thereby, I wasn't really functioning that well and just became a pawn for them. I hope that I would be reunited with my old group the next meeting.

I realized this meeting that it is very difficult for me to work with people I barely know.

On Technical Paper Writing

January 21, 2011; 8:30-11:30; NIP R108

Technical paper writing is one thing a good physicist must be adept at doing. For one to publish his findings, he must be able to communicate his ideas properly by following the recommended format set by the scientific community. It is important that I, as an aspiring physicist, to become an excellent technical paper writer.

Last meeting, we performed an experiment to find the value of g (~9.8 m/s^2) by using the air track set-up. We were tasked to write a technical paper that documented our findings.

We were taught the different elements of a technical paper (title, abstract, contents, nomenclature, chapters (composed of introduction, review of related literature, methodology, results, analysis, conclusion and recommendation), references and appendices). Sir Pacho also introduced us to the SPP (Samahang Pisika ng Pilipinas).

Everything this meeting was very reminiscent of high school science. In my HS, we were required to submit a technical paper once a year- each for integrated science, biology, chemistry and physics, and we were also given general guidelines to follow as to practice uniformity. It was something I admittedly dreaded doing, mainly because writing that kind of paper was very monotonous- I prefer creative writing. But still, I know that it is a MUST that I learn to appreciate it to become an awesome physicist.

On Air Tracks and Experimentation

January 14, 2011; 8:30-11:30; NIP R108

This meeting's goal was basically to gather experimental data from an air track (which is virtually frictionless) set-up wherein a cart was pushed (with constant force- using a retractable pen) a variable distance (from 5 m to 45 inches close to the other end), taking note of how long it would take to complete its travel. The angle of the air track was also another manipulated variable (which was done by stacking books one on top of the other).

We were quite late this meeting because we rushed the lab report for the activity prior to this meeting. When we entered the room, our classmates were already gathered around the air track doing the experiment. I was assigned to record the time it took for the cart to reach the other end for a while but I was unable to try actually pushing the cart.

From raw experimental data, it became evident that the farther the distance from one end, the longer it took for the object to reach the other end. Applying a constant force in a frictionless surface entails that the acceleration of the object applied with the force is constant. Its velocity would increase in x increments per unit second. It was also evident that increasing the angle's measure would make it quicker for the object to reach the other end (due to the acceleration due to gravity).

The lab meeting was quite fast since the activity wasn't really that demanding. I realized this lab meeting that I knew only a handful of my classmates personally, and that I should be more sociable as to be able to enjoy the lab meetings in its entirety.