2024 Physics Capstone Symposium

Senior Physics capstone presentations will take place Monday, May 6th starting at 2pm in Rieke 103B. 

2:10pm
Julian Kop – “Using Python to Mathematically Model Variable Star Light Curves.”
Constructing light curve plots of stellar brightness can describe various stellar properties and the systems these stars reside. Variable star light curves possess unique trends and modeling these light curves can denote long-term behavior and changes to variability. However, variable stars are affected by various different phenomena, and hence it requires different equations to model these varying trends in the light curves. Creating light curves and applying mathematical models was most easily done using the coding program Python, which was greatly reliable with many data manipulation and modeling libraries and packages. Variable star light curve data was acquired from the ASAS-SN atlas database and was subsequently applied with theoretical mathematical formulae. Assorting through various formulae in Python assisted in determining model parameters, their uncertainty, and their reduced χ2 for several variable stars. The reduced χ2 values were quantitative determinants of which models proved significantly the best-fits for the light curves.

2:30pm
Jessica Ordaz – “Stars Across the Ages: Investigating Stellar Evolution, Population Dynamics, and Metal Content.”
How exactly do astronomers determine the ages and composition of stars? Because of the nature of space, meaning the vast distances and non reproducible environment, I wanted to investigate how astronomers obtain this information about our universe. I explore and summarize the theory and experimental process that has already been implemented and published regarding the evolution of a star and how we determine the ages of stars using both Hertzsprung-Russell diagrams and absorption spectra (which is linked to metallicity). When specifically looking at the sun, the tools astronomers use are in depth, specific, and accurate and they are able to determine both the elements present in the sun as well as their abundances and these values are used to calculate relative ages of both our sun as well as other stars. Through this experiment and its results, we can peer through to the formation of the universe, its stars, and its galaxies to learn more about the space we inhabit.

2:50pm
Ryan Stracke – “High School Physics Harmonic Motion Lab Using Model-Building.”
The motivation for this project is to create a high-school physics lab which will be more engaging than the typical lab. It will allow students to use the scientific process to explain the relationship between spring constant, attached mass and frequency. The problem is creating a lab which actively engages students, rather than just having students follow a given procedure. This can be solved by using model-building in the experiments rather than model-confirming. This allows students to follow a more realistic process. The designed lab will give students the chance to create models for the involved phenomena themselves, which will give them a better understanding of the material and more responsibility over their own work.

3:10pm Break

3:30pm
Colton Schmidt – “Transconductance and Transistors”
Transistors are an integral part of our society and one of the most basic building blocks of our technology. However, I would not call them basic. Of the many types of transistors out there, I wanted to focus on studying the most common; the metal-oxide-semiconductor field effect transistor (MOSFET). I performed a consumer review of a BS170 MOSFET to verify its threshold voltage and transconductance. After several iterations of experimentation, my research culminated in the use of a function generator and an Arduino, backed up with a model simulation using the industry standard circuitry software, LTSpice. I am currently hoping to get the data analyzed to see if the threshold voltage of my device is equivalent to the manufacturer’s reported value of 2.1 volts. This should help give other consumers a better understanding of the device and give them an idea of what range of use the transistors have.

3:50pm
Cody Ahn – “Strings in Action! Unraveling the Impact of Tennis Racket Tension on Elasticity in Ball-Racket Collisions.”
As a sports fan, tennis is one of the most entertaining racket sports of all time. As a former tennis player, it is extremely interesting to see how the ball responds to certain hits from the racket which also depends on where it hits certain points of the string bed of the racket, the string material, the string tension, and the different angles within the swing of the racket. The main issue/problem is that the experiment requires numerous data points with string tensions and where the ball specifically lands on the racket, especially with the coefficient of restitution (COR) that counts for every collision. Using in physical experiment, it was possible to gain data points measuring the height of the drop and the recovery of the ball after the collision of racket strings. Using a camera to determine the specific/accurate points to measure x and y of the plot. Results have not yet been solved, but it is safe to say that the correlation between the two can be very formally understood according to the data points. Understanding this topic can not only help tennis players to evolve and improve their performance but also for the fans who love to watch the sport and understand the physics aspect of what is truly happening in front of their eyes.