Experiment of The Month

Our labs do not have written instructions. In keeping with this spirit, the description given here will be brief and general. The intent is that each performance of the lab will be unique; in each nature will reveal a slightly different face to the observer.

The senior seminar experience covers two semesters at Millersville. In the first semester, the student selects an advisor and decides on the nature of his or her project. The majority of the semester is spent developing the analytical and (often) experimental tools necessary to complete the project. Ideally, by the end of the first semester, the first results are in hand.

During the semester, students give regular, short, reports to the seminar audience. These reports initially are used to invite ideas from the audience for aspects of the project that would be interesting to understand further. By the end of the semester, the reports are about 20 minutes in length, and include a modest paper report as well.

During the second semester, the project is typically modified in view of the results of the first semester. Ideally, the research component is complete by mid-semester. The semester ends with a 30 minute talk and an extensive paper report. Ideally, the second half of the semester is spent polishing the talk and report; following new ideas and tying down loose ends.

A separate component of the second senior seminar semester is devoted to the Major Field Test; a comprehensive examination in physics. The exam is 2 hours in length and is provided by the Educational Testing Service. It is similar in style to the Graduate Record Exam for physics, but is shorter and somewhat less demanding. The exam results contribute to the grade for the second semester. It is used as a raison d'etre for a comprehensive review of four years of physics, centered around a collection of typical graduate record exam questions.

This spring, four students finished their first semester's work. Their beginnings promise an interesting collection of seminars for the fall semester. The abstracts for their paper reports are copied below.

Jeff Moyer: The physics of the collision between the baseball and the baseball bat was explored. Equations of motion were found for the collision, and they were used to determine the resulting speed of the ball after the collision, the spin on the ball, and the angle at which it left the bat. These were done for a simple diagram of a bat hitting a ball on a tee. Future effort will aim to understand the creation of rotational motion in the batted ball.

Harry Nash: When a volume of water in a cylindrical vessel rotates about a fixed vertical axis, the shape of the volume becomes parabolic. Using a force diagram, I have derived the equations which describe the shape of the volume while it undergoes rotation about the vertical axis. I have observed the fluid in the laboratory environment under these conditions and have visually confirmed the parabolic prediction. My goal is to measure the (optical reflection) focal length of these parabolas at varying rotational speeds. In order to do this, I must minimize the vibration in my system.

Dave Neidig: The primary focus of this project is to show experimentally the existence of quantized conductance in homemade relay contacts. Measurements to date show no conclusive evidence of quantization. Experiments so far have been on small surface-area copper contacts. They will be extended to use gold contacts.

Tim Atherton: In my experiment, I am studying plasma inside of a gas discharge tube. In a tube about 1 meter long, with 3000 volts applied end-to-end, I pumped the air out and, when the pressure was low enough, I observed glow discharge in the remaining gas. Under different conditions, with 5000 volts applied, I observed a separate phenomenon, called the luminous arc. I intend to observe the effect of polarity changes and magnetic field on the discharge, and to understand the phenomena in terms of the mean free path of the ions and electrons in the plasma.