Physics Commons^™

An Analysis Of Energy Production And Efficiency In Various Longbow Archery Models, Hannah Mcpherson

Honors Projects

An analysis of the energy production and efficiency of three lab-tested longbow models is undertaken. The first model, which is constructed to not allow flexing of limbs and which uses a frictionless cart and track in place of an arrow, demonstrated an efficiency of 50% +/- 40%. The second model, which is constructed similarly to the first with the exception of a wooden dowel now being used as an arrow-like object, demonstrated an efficiency of 13% +/- 3%. The last model, a 3D printed longbow with flexible limbs using the wooden dowel as an arrow-like object, demonstrated an efficiency of …

Statistical Comparison Between Observational Data And Simulated Gravitational Waves, Matthew Gordon

Honors Projects

The goal of this project is to determine the effective accuracy of a simulation that graphs the gravitational waves emitted from a binary system. The Python program that creates these graphs uses different analytical models to approximate each phase of the model, inspiral and merger. Data from the Gravitational Wave Open Science Center (GWOSC) website regarding an observed event is used to compare to the output of the simulation. Another Python program matches up the two waveforms and calculates a correlation coefficient between the two, which is close to 1, as desired. Additional graphs are simulated using masses that differ …

Improving 3d Printed Prosthetics With Sensors And Motors, Rachel Zarin

Honors Projects

A 3D printed hand and arm prosthetic was created from the idea of adding bionic elements while keeping the cost low. It was designed based on existing models, desired functions, and materials available. A tilt sensor keeps the hand level, two motors move the wrist in two different directions, a limit switch signals the fingers to open and close, and another motor helps open and close the fingers. All sensors and motors were built on a circuit board, programmed using an Arduino, and powered by a battery. Other supporting materials include metal brackets, screws, guitar strings, elastic bands, small clamps, …

Terahertz Absorption Spectra Of Silicate Cosmic Analog Dusts Using A Novel Spectrometer, Binh Phan

Honors Projects

Metal-containing amorphous silicate grains are expected to be a major component of interstellar dust. Amorphous silicate grains containing magnesium, iron, and calcium have been synthesized in the IWU chemistry department. I have contributed to the construction and testing of an instrument that will be used to measure terahertz absorption spectra of cold samples at astronomically interesting temperatures.

To study cosmic dust analogs, we installed dust samples, embedded in low-density polyethylene (LDPE) pellets, in a sample-exchanger and cooled it down within a cryostat to 3.0 Kelvin. Using a blackbody radiation source, we measured the transmission of terahertz light through those samples …

Studies In Mesoscopics And Quantum Microscopies, Zhenghao Ding, Gabriel C. Spalding

Honors Projects

This thesis begins with a foundational section on quantum optics. The single-photon detectors used in the first chapter were obtained through the Advanced Laboratory Physics Association (ALPhA), which brokered reduced cost for educational use, and the aim of the single-photon work presented in Chapter 1 is to develop modules for use in Illinois Wesleyan's instructional labs beyond the first year of university. Along with the American Association of Physics Teachers, ALPhA encourages capstone-level work, such as Chapter 1 of this honors thesis, which is explicitly designed to play the role of passing on, to a next generation of physics majors, …

Visualizing A Fourth Dimension: Hypercubic Resistor Networks, Andrew J. Nelson '08

Honors Projects

A booming field in physics research today is the search for extra dimensions. This is something that has been thought about and discussed in both the scientific and non-scientific world for a long time. Many physicists are currently attempting to answer the question: "is our world really four dimensional?" The purpose of this research, however, is not to answer that question. The purpose of this work is to help reveal four-dimensional artifacts in our perceived three-dimensional world in order to help a student, even a non-physicist, to understand and visualize how the extra spatial dimensionality, if present, might reveal itself …

The Vibrational Behavior Of A Cured Carbon Fiber Disk And A Tennis Racket, Nick Timme '08

Honors Projects

In this project the vibrational behavior of a circular cured carbon fiber plate and a tennis racket is examined using a speckle-pattern interferometry system built and designed by students at Illinois Wesleyan University. Specifically, the mode shapes and mode frequencies are presented and discussed. With regards to the carbon fiber plate, the effects of the orthogonal construction of the plate on the vibrational behavior are studied. With regards to the tennis racket, the mode shapes of the racket are imaged for the first time using speckle-pattern interferometry. Furthermore, the effects of commercially available vibration dampers on the vibrational behavior of …

Photometry Of Outer-Belt Objects, Gautham S. Narayan '05

Honors Projects

We present results from multi-wavelength observations of outer-belt asteroid 279 Thule and comet C12002 CE10 (LINEAR). The orbital elements of the second object, formerly classified as asteroid 2002 CE10, at first led to its identification with a group of asteroids called the Damocloids. The Damocloids' orbits are similar to Halley family comets (HFCs), and there is suspicion that the Damocloids are inactive HFC nuclei. Following observations by the 8.2 m Japanese Subaru telescope in August 2003, which determined that 2002 CE IO had a characteristic tail (Takato et al; 2003), it was re-classified as comet C/2002 CE10 (LINEAR). We observed …

Phase Transitions Occurring In Models Of Neighborhood Racial Segregation, Alexander J. Laurie '03

Honors Projects

This thesis is organized as two chapters whose contents are closely related yet quite distinct. The first chapter presents a paper "Role of 'Vision' in Neighborhood Racial Segregation: A Variant of the Schelling Segregation Model," authored by myself and Dr. Jaggi, which has been accepted for publication by the journal Urban Studies and is currently in press (as of April 2003). This chapter introduces the well-known Schelling model of neighborhood segregation, outlines the sociopolitical motivation for our work, and presents the key results that we believe are of interest to social scientists. Chapter two, which ought to be of greater …

Design And Construction Of A Radio Frequency Plasma Device, Matthew Highland '02

Honors Projects

We have constructed a radio frequency plasma device to study a wide range of phenomena including, power coupling between the plasma and the antenna and wave propagation. Our system includes a high vacuum chamber with mechanical and diffusion pumps, a radio frequency source magnetic field coils and a matching network.

Development Of A Data Acquisition And Analysis System, Michael V. Mores '02

Honors Projects

Plasma is the fourth and least understood state of matter. A more complete understanding of this state of matter has numerous practical applications, including fusion energy, space travel, materials synthesis, and thin film deposition. As such, there is an obvious motivation to study this state. To do this, we have constructed a radio-frequency plasma device at Illinois Wesleyan University. I have developed a data acquisition using LabVIEW software that can digitize eight analog signals, saving the data to disk for later analysis. I have also written analysis software using LabVIEW to extract meaningful information from Langmuir Probe Trace.

Holographic Optical Tweezers: Development And Analysis Of The First Holodeck Prototype, Matthew T. Dearing '00

Honors Projects

Tightly focused light can be used to non-invasively trap and manipulate micro-objects, a technique called "optical tweezing." By utilizing the large field gradients present in a focused laser beam, micro-particles-including biological specimens and many other materials-can become confined in all three dimensions. While optical tweezing has existed for over a decade, it has generally been limited to trapping one or two particles at a time. We have developed a technique that uses laser light to assemble large numbers of micro-particles in a highly controllable way. Here we describe, for the first time, the complete implementation of holographic optical tweezer arrays …

X-Ray Spectroscopic Mapping Of Three Unusual Active Galaxies (Ngc 4258, Ngc 1097, And Ngc 1068), Jeremy Kotter '98

Honors Projects

One enigmatic class of objects whose structures are interesting and only recently explored are active galactic nuclei (AGN). These are galaxies in which massive black holes sit at the center and accrete matter. The term "active" refers to energetic processes which are not directly attributable to stars and which occur in the innermost portions of galaxies. Astrophysicists have developed general descriptions of AGN, but details about these objects remain incomplete. Notably, the thermal and ionization structures of AGN accretion disks and the geometries of the circum-source clouds which surround the black hole and comprise an important portion of the energy …

Harmonic Oscillation In The Presence Of Multiple Damping Forces, Chris Pelto '97

Honors Projects

The relatively mundane damped harmonic oscillator is found to exhibit interesting motion once under the influence of both a velocity dependent and a Coulombic frictional damping force. Data for the decay of the amplitude as a function of time were collected on a specially prepared torsional oscillator. with a variable electromagnetic damping mechanism. An analytical solution of the appropriate equation of motion was obtained by the method of Laplace transforms. In both the limits of zero Coulombic friction and zero velocity damping, the solution reduces to the well-known answers to the problem. the solution, when plotted with the correct parameters, …

On The Mechanism Of Giant Electromotility In Polyelectrolyte Gels, Kimberly Ann Branshaw '95

Honors Projects

Electromotility, i.e. bending in response to an electric field, of polyelectrolyte gels in ionic solutions has recently been investigated at a few leading academic and industrial labs as a potential chemomechanical engine. We have discovered that the underlying physics in these systems is more complex than previously believed. We have found that the bending, which seems to obey a {t power law, is inconsistent with the simple idea of a bending speed, but is consistent with a diffusion mechanism. Evidence of diffusion was independently provided by experiments on gels grown or bent in the presence of dyes. We have explored …

Novel Swelling Structures And Electromotility Response In Polyelectrolyte Gels, Dana Deardorff

Honors Projects

Electromotility, the bending in response to an electric field, of polyelectrolyte gels in ionic solutions has been identified as a candidate for a potential chemomechanical engines such as muscles. We discovered that the underlying physics of these systems is more complex than previously believed. We found that the bending as a function of time obeys a square root power law. This points strongly towards a diffusion mechanism for the bending. Kinetic evidence for diffusion was independently corroborated by experiments on gels grown or bent in the presence of dyes. We explored the effects of varying poly-ion concentration in the backbone …

A Lattice Gas Approach To The Structure And Dynamics Of Electrorheological Fluids, Jie Chen '93

Honors Projects

Electrorheological fluids consist of a colloidal suspension of dielectric particles in a continuous fluid of smaller dielectric constant. Molecular dynamics simulations of these fluids in an applied electric field have recently been shown to produce percolated, columnar structures. No systematic attempt has been made so far to simultaneously include the effects of temperature and the viscous drag due to the continuous fluid. We propose a dipolar lattice gas model for electrorheological fluids and study the resulting structures and dynamics. We attempt to incorporate the effect of the viscosity of the continuous medium by a dynamic ansatz that determines the range …

A Novel Technique For Studying The Shear Elastic Properties Of Weak Solids, Jason A. Payne '93

Honors Projects

We have developed a simple, inexpensive, and precise technique to measure the shear elastic modulus of weak solids using electromagnetic and optical tools. This technique can be easily adapted to measure the viscosity of a liquid also. A Helmholtz pair was used to produce a torque on a permanent magnet mounted on the smaller of two concentric cylinders, coupled by the material to be studied. The torque was controlled precisely and measured accurately in terms of the current flowing through the coils of the Helmholtz pair. An optical lever was employed to measure the angular displacement of the inner cylinder …

Deflection Of An Electron Beam By Photons, Danning W. Bloom '64

Honors Projects

The purpose of this paper was to review information, both experimental and theoretical, concerning the momentum carried by light and its effect on free electrons.